Preheat the oven to 425° and line a rimmed sheet pan with parchment paper.
Slice the potatoes into 1/4" thick rings and add the sheet pan. Drizzle with 1 tablespoon of oil and sprinkle with 1 1/2 teaspoon salt and pepper. Toss the potatoes to evenly distribute the seasoning and lay out in a single layer on the sheet pan.
Bake for 30-32 minutes, until the potatoes are golden brown across the tops. While the potatoes are baking, fry the bacon and make the cheese sauce.
Add the diced bacon to a large pan over medium-high heat. Cook, stirring occasionally, until the bacon is crispy, 6-8 minutes. Set bacon aside on a plate lined with a paper towel.
For the cheese sauce, add 1 tablespoon of oil to a saucepan over medium heat. Allow to come to temperature and sprinkle over the flour. Whisk about 1 minute. Do not allow the flour to brown.
Begin adding the half-and-half one generous splash at a time, whisking well after each addition. Once all of the half-and-half has been added, allow the mixture to simmer 4-5 minutes, just until slightly thickened.
Remove from the heat and stir in 1 cup of Cheddar cheese and a generous pinch of Kosher salt. Set aside.
Remove the potatoes from the oven, drizzle with the cheese sauce, cheese curds (if using), the remaining 1/2 cup of Cheddar, and diced bacon.
If desired, return to the oven for 4-5 minutes, just until the cheese curds have melted. Top with sliced green onions and sour cream (if using), serve, and enjoy!