Nonstick cooking spray
2 pounds medium russet potatoes (about 4 potatoes)
2 large red potatoes (8 ounces total)
1 1/2 teaspoons kosher salt, plus for seasoning
1/2 teaspoon freshly cracked black pepper
1 tablespoon all-purpose flour
2 tablespoons olive oil
Ketchup and mustard, for dipping