In a large bowl, whisk together the flour, baking powder, sea salt, sugar, and black pepper. Add the milk, egg, sour cream, and melted butter, and fold until just combined. It’s okay if your batter has a few lumps!
In a small bowl, combine your shredded and grated cheeses, and set aside.
In a large skillet over medium heat, melt a generous amount of butter. Once the pan is hot, ladle in roughly 1/3 cup of batter. Cook until small bubbles appear on top and the bottom is golden brown. Flip and cook the second side, then remove from the pan and place on a small plate.
Start another pancake in the skillet. As soon as you flip the second pancake, sprinkle about 3-4 tablespoons of your cheese mixture on top (more or less, depending on how cheesy you want it). Cover the pan to help the cheese melt quickly.
Once the cheese is melted and the bottom of the pancake is cooked, place the first pancake on top of the melted cheese, forming a sandwich.
Remove the finished pancake stack from the skillet and place it on a serving plate. (See notes below for how to keep pancakes warm if you’re not serving them immediately.)
Repeat with the remaining pancake batter and cheese mixture. You should end up with about 4–5 pancake cheese sandwiches.
Serve your grilled cheese pancakes immediately, topped with crumbled bacon and maple syrup. (and any leftover cheese blend!)
Enjoy!