Description
The ultimate comfort food side dish featuring layers of thinly sliced Yukon Gold potatoes baked in a creamy garlic and thyme sauce, topped with golden melted cheddar cheese. Perfect for holidays, family dinners, or any time you want to treat yourself to something special.
Ingredients
For the Creamy Sauce:
- 3 tablespoons unsalted butter, plus extra for greasing the pan
- ¼ cup all-purpose flour
- 2 cups whole milk
- 1 cup vegetable broth
- 4 garlic cloves, grated
- 1 tablespoon fresh thyme leaves, chopped
- 2 teaspoons sea salt
- ½ teaspoon freshly ground black pepper
For the Layers:
- 3 pounds Yukon Gold potatoes, sliced about 1/8-inch thick
- ½ medium yellow onion, thinly sliced
- 1½ cups grated cheddar cheese
Instructions
Heat oven to 400°F. Butter your 9×13 dish real good – don’t be stingy here.
Melt your butter in that skillet – don’t walk away because butter goes from perfect to burnt in like two seconds. Dump in the flour and whisk like your life depends on it. Cook it for a minute until it smells kinda toasty. This part used to scare me but now I know it’s what stops your sauce from tasting like paste.
Pour in the milk super slow – I learned this the hard way when I dumped it all in at once and got lumpy disaster sauce. Add the broth, keep whisking. Toss in that grated garlic, thyme, salt, and pepper. Stir it around for a couple minutes until it’s thick enough that it sticks to your spoon a bit. Done.
This part’s actually fun once you get the hang of it. Take half your potato slices and lay them in the buttered dish – overlap them a little so it looks neat. Scatter half the onions on top, pour over half that gorgeous sauce you just made, then sprinkle a cup of cheese.
Do the whole thing again – more potatoes, rest of the onions, rest of the sauce, then that last bit of cheese on top. My kids always want to help with this part because it’s like building something edible.
Slap some foil on top and stick it in the oven for 30 minutes. Then rip off the foil and bake another 35-40 minutes until you can poke the potatoes easily with a fork and that cheese on top looks like something from a restaurant.
This is where I used to mess up every single time. You gotta let it sit for 20 minutes before you cut into it. I know it’s torture when your kitchen smells amazing and everyone’s hovering around, but if you cut too early, you’ll get a soupy mess instead of nice clean slices. Trust me on this one.
Notes
- Get obsessive about slice thickness – I’m talking 1/8-inch, people. Too thick and the centers stay crunchy; too thin and you get potato mush soup.
- Don’t skip the roux step – cooking that butter and flour for a full minute gets rid of the weird raw flour taste that ruins everything.
- Overlap those potato slices like you’re shingling a roof. It looks pretty and makes sure everything cooks evenly.
- The foil is your friend – cover first to steam the potatoes, then uncover to get that gorgeous golden top that makes everyone think you’re a kitchen genius.
- Prep Time: 20 minutes
- Cook Time: 65-70 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: American