A perfect side dish for any occasion, this Homemade Cheesy Scalloped Potatoes is going to be showstopper! It's simple and packed with great flavors!
Preheat the oven to 375F. Coat an oven safe dish with nonstick spray.
Place a saucepan on the burner and turn the heat on. Add butter to the sauce pan, once it's almost melted, add the olive oil.
Add in the flour, stir until it smells a little bit nutty, for about 3 minutes.
Add in onion and garlic powder, stir for one minute.
Add 1/4 cup milk, mix well until it forms a paste, then add the milk slowly and gradually until all is added. Stir constantly to avoid lumps.
Stir and cook until the sauce thickens a little bit just enough that it's not watery anymore.
Slice the red potatoes evenly, make sure all the slices have the same thickness.
Arrange the potato slices in the oven safe dish in circles, overlapping in a single layer.
Sprinkle shredded white cheddar all over the potatoes.
Pour the white sauce you made in the sauce pan over the potatoes, make sure they're covered.
Sprinkle Parmesan cheese on top. Cover with aluminum foil.
Bake in the oven for 40 minutes covered. Then uncover and bake for an additional 30 minutes until potatoes are fully cooked and the sauce is golden and bubbly.
Slow cooker scalloped potatoes: Follow the recipe as instructed. Coat the bottom of the slow cooker with a cooking spray and arrange the potatoes at the bottom of the slow cooker, overlapping in a single layer and top with cheese and the sauce. Top with parmesan and cook on high for 4 hours or until the potatoes are fully cooked.