potato and onion casserole with chopped scallions as a garnish

POTATO AND ONION CASSEROLE

Potato and onion roasted in garlic butter is simple and delicious

Let your oven do all the work

Potatoes and onions are a tried and true pairing, and our potato and onion casserole makes the most of the dynamic duo. They are both root vegetables and abundant in all varieties in the fall just as we are starting to use the oven again for dinners. Using your oven to make dinner can really free up some time. If there’s anything better than making your main course an easy fix by oven cooking, it’s popping a side dish in to cook at the same time. This potato and onion casserole checks all the boxes. It’s quick, easy, delicious and uses ingredients that you probably already have on hand.

Less than 5 minutes prep time

Roasted dinners of any kind usually don’t take a lot of time to get ready for the oven, but this potato and onion casserole takes even less time than most. The garlic butter sauce is simply butter, garlic, salt and pepper melted together in the microwave for 1 minute on defrost. There is no need to peel the potatoes, just chop them up in bite sized pieces. The skins add nutritional value and flavor. Slice a peeled onion in lengthwise strips, mix everything together and pop it in the oven. That’s it!

Potato onions and butter gives you a blank canvas

Most of us who enjoy cooking use it as a way to be creative. This potato and onion casserole is a dish that makes it easy to experiment with flavors. It is like a blank canvas, waiting for you to give it a personal touch. In this recipe we are using fresh garlic, salt and pepper to flavor the butter sauce. But potato and onion have a flavor profile that can be complemented by countless herbs and oils. Try adding the flavors you are using in your main course. Use other vegetables or fruits in your casserole. You can add spices you like. This dish is easy to make your own.

Potato and onion casserole is another “bail me out” recipe

I am not good at planning ahead, and have had to learn to co-exist with my shortcomings. As far as cooking dinner goes, that has meant having a stock pile of “bail me out” recipes.

My “bail me out” recipes are ones that can be made from ingredients I always have on hand. Potatoes, onions, butter and garlic are on that list. The little time this potato and onion casserole takes to prepare for the oven comes in handy too. No planning, no problem.

It is economical and down right tasty too. Bet you don’t make it only once!

Want more “bail me out” recipes?

If you are looking for another bail me out recipe we have our BASIC FRITTATA. All you need for that is potatoes, onion and eggs. Or keep some canned tomatoes and pasta stocked so you can make a delicious quick MARINARA SAUCE pasta dinner in about 15 minutes. Make your own Garlic Bread to serve on the side of either of these meals and you have a meal fit for a king in about a half hour.

Here’s what YOU WILL NEED:

ingredients for potato and onion casserole potatoes onion garlic butter salt and pepper and scallions
3-4 medium sized potatoes we are using yukon gold
1 medium yellow onion
3 cloves of fresh garlic or more depending on size of cloves
6 tablespoons butter (3/4 of a stick)
1/2 teaspoon salt
1/2 teaspoon pepper
2-3 scallions for garnish optional to add a little texture and freshness
Ingredient tidbits: About Onion, About Scallion, About Garlic, When we say Potato

Make it your way

This is where your creativity begins; the ingredients. This recipe is an easy one to adapt to what you like.

Potatoes

This time around, I am using Yukon gold potatoes. They hold up well when cooked and they are rich and delicious.

You can use any potato you like. Adjust for the difference in size, using more if they are small, or less if they are large.

I don’t bother peeling the potatoes for dish like this. There’s a lot of nutrients in the potato skins, so why peel them off? People are paying a lot of money for potato skins these days. And let’s face it, it is easier to leave them unpeeled. Wash them well first. We have a whimsical post about what may be lingering on your unwashed fruits and vegetables Wash Before You Eat.

Onions

This dinner recipe calls for a yellow onion. Those are the ones most common in our area. They are one of the stronger tasting onions. Sweet or Vidalia onions are milder, and great in this dish too. We would stay away from red onions for this recipe. When they cook for a while, they become pretty bland.

Another thing about red onions. Not in this recipe, but sometimes red onions will turn a sauce or soup blue when used with certain other ingredients. They are delicious raw in salads and dips. We have a COOKING TIDBITS post with pictures of various common onions if you are not familiar with them, take a look About Onions.

Herbs and spices

As for the garlic butter sauce, you can use any flavoring you want in the butter, or none at all. Butter, salt and pepper is all you need.

Potatoes are great with rosemary, thyme or parsley, but you may like another herb. If you are roasting or baking your main course at the same time, add the same flavor profile to your potato and onion casserole.

I use dried herbs in this recipe, because it will be cooking long enough to rehydrate them and we will get all that concentrated flavor.

I sprinkled some fresh Scallions over the top before serving. They have a bright, fresh subtle onion taste which can give a cooked dish like this potato and onion casserole a variety in texture.

This is WHAT TO DO:

Preheat oven to 350 degrees.

Chop, slice and mince

Do you know those terms? If you want to know more about the what, when and why take a look at our post Slice Dice Mince and Chop.

chopped potatoes sliced onions and chopped scallions and garlic

Chop the potatoes into bite sized pieces. The larger the pieces, the longer they will take to cook. Also, smaller sized pieces let you get a better mix of ingredients on your plate.

Slice the onion in by cutting it in half lengthwise first and then putting the cut end flat on the cutting board and cutting the slices from top to bottom.

Mince the garlic. And slice the scallions greens into small pieces for garnish.

chopped potatoes and sliced onions in a casserole dish

Mix the potatoes and onions in a baking dish. Bake them in a dish large enough so the vegetables are not heaped up on top of each other. That would cause them to steam instead of roast.

butter salt pepper and garlic in a microwave safe cup ready to be melted

To make the garlic butter sauce, cut the butter into cubes and put them in a small dish. Add the chopped garlic, salt and pepper and melt it in the microwave. I used the defrost setting (50%) for one minute.

I bet you know what comes next.

potatoes and onions are coated with the garlic butter sauce

Stir the melted butter sauce, pour it over the potato and onion and mix it in so the vegetables are covered in the sauce.

Now all you have to do is put it in the oven

After mixing the butter garlic sauce into the potato and onion in the baking dish, put it in the preheated oven for 45 minutes or until the potatoes are tender.

Check on your casserole after 30-35 minutes to see if the potatoes are tender. Depending on the size of the potato pieces, the size of the baking dish you are using and the type of potato, cooking time can vary.

Done

potato and onion casserole just out of the oven

And here is your side dish of potato and onion with a garlic butter sauce, right out of the oven. And remember it took less than 5 minutes to get it ready for the oven!

Serve

Potato and onion casserole in a garlic butter sauce with fresh scallion used as a garnish for color and texture.
potato and onion casserole with chopped scallions as a garnish

POTATO AND ONION CASSEROLE

Claudia
Potatoes and onions roasted in a garlic butter sauce makes a delicious side dish and takes less than five minutes to prepare for the oven.
No ratings yet
Prep Time 5 minutes
Cook Time 45 minutes
Total Time 50 minutes
Course Dinner, Lunch, meatless meal
Cuisine American
Servings 4
Calories 192 kcal

Ingredients
  

  • 4 medium potatoes yukon gold or what you have on hand
  • 1 yellow onion medium sized
  • 3 cloves fresh garlic
  • 6 tablespoons butter ¾ of a stick
  • ½ teaspoon salt
  • ½ teaspoon pepper
  • 3 scallions also called green onion for garnish

Instructions
 

Prepare Ingredients

  • Chop washed unpeeled potatoes into bite sized pieces.
  • Slice a peeled onion in half lengthwise and laying the cut side down slice lengthwise.
  • Finely chop (mince) the garlic cloves.
  • Cut the butter into cubes so it will melt faster and more uniformly.
  • Slice the green scallion stems for garnish (optional)

Cooking Instructions

  • Preheat oven to 350 degrees.
  • Put the butter cubes, garlic, salt and pepper in a small bowl or cup. Melt it all together in the microwave. I use defrost power for 1 minute.
  • Put the cut potato and onion in a baking dish.
  • When the butter mixture has melted, stir it up and pour it over the potato and onion, Mix it in so the vegetables are coated with the butter sauce.
  • Bake for 45 minutes. Check it after 30 minutes to see if the potatoes are tender. They could be done if your dish is large, or your pieces are small. If the potatoes are not done, return the dish to the oven for the remaining 15 minutes.
  • Remove from oven and serve.

Nutrition

Calories: 192kcalCarbohydrates: 42gProtein: 6gFat: 1gSaturated Fat: 1gPolyunsaturated Fat: 0.2gMonounsaturated Fat: 0.2gCholesterol: 2mgSodium: 330mgPotassium: 995mgFiber: 5gSugar: 4gVitamin A: 133IUVitamin C: 46mgCalcium: 66mgIron: 2mg
Keyword 5 ingredients or less, autumn meals, baked vegetable side dish, easy to make, potato and onion casserole, potato side dish, side dish for roasts, side dishes for the oven
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