Drop quarter cups of batter onto the preheated pan. Cook until bubbles start to appear on the exposed surface of the pancake. When bubbles appear, flip pancake and cook for an additional 2-3 minutes or until browned. Remove to a wire rack and allow to cool. Repeat with remaining batter.
In the morning, preheat the oven to 350 degrees. Whisk together the flour, oats, pecans (optional), brown sugar, salt, and cinnamon. Pour the melted butter over top and stir. Use your fingers to work the mixture until crumbs form. Pour the crumbs evenly over the top and bake for 45-50 minutes or until the crumbs are browned and center if fully set.
You can use any pancakes for this recipe, though I’ve included my favorite recipe here. You’ll need about 20 pancakes for the casserole.