Ingredients:
- 2 tbsp (28g) Unsalted Butter
- 0.5 cup (75g) Yellow Onion, finely diced
- 4 cloves Garlic, minced (about 1.5 tbsp)
- 1 tbsp (8g) All-purpose Flour
- 1.5 cups (350ml) Heavy Cream
- 0.5 cup (120ml) Whole Milk
- 1 tsp (6g) Fine Sea Salt
- 0.5 tsp (1g) Freshly cracked Black Pepper
- 0.25 tsp (0.5g) Cayenne Pepper
- 2.5 lbs (1.1kg) Russet Potatoes, peeled and sliced into 1/8-inch rounds
- 1.5 cups (170g) Sharp Cheddar Cheese, freshly shredded
- 0.5 cup (45g) Grated Parmesan Cheese
- 2 tbsp (15g) Velveeta or American cheese, diced
Instructions:
- Preheat your oven to 375°F (190°C). Generously butter a 2-quart baking dish. Peel the Russet potatoes and slice into uniform 1/8-inch rounds. Submerge in cold water to prevent oxidation, then pat completely dry before use.
- In a large heavy-bottomed saucepan or Dutch oven, melt the butter over medium heat. Sauté the diced onion for approximately 4 minutes until translucent.
- Add the minced garlic and cook for 60 seconds until fragrant. Sprinkle the flour over the onion and garlic mixture, whisking constantly for 1 minute to create a blonde roux.
- Slowly whisk in the heavy cream and whole milk, ensuring no lumps remain. Season with sea salt, black pepper, and cayenne pepper.
- Bring the cream mixture to a gentle simmer. Add the dried potato slices and cook for 3-5 minutes on the stovetop. This releases the potato starch into the sauce for a thicker consistency.
- Remove from heat and fold in the sharp cheddar, Parmesan, and Velveeta until the cheese is melted and the sauce is smooth.
- Transfer the mixture into the prepared baking dish. Spread evenly and bake for 45 minutes, or until the potatoes are fork-tender and the top is golden brown and bubbling.