Make the pancake batter: In a large bowl, whisk together flour, sugar, baking powder, and salt. In another bowl, beat the eggs, then add milk, melted butter, and vanilla. Pour the wet ingredients into the dry and stir just until combined. Don't overmix—lumps are your friends here.
Prep the sausage: Place the sausage in a bowl, add the maple syrup, black pepper, and cayenne if using. Mix gently with your hands until just combined. Divide into 12 equal portions and flatten into patties slightly larger than silver dollar size (they'll shrink when cooking).
Cook the sausage: Heat a large skillet or griddle over medium heat. Cook the sausage patties for about 3-4 minutes per side until browned and cooked through (internal temperature of 160°F). Transfer to a paper towel-lined plate to absorb excess grease.
Make the pancakes: Wipe down the skillet (or use a clean one if you have it), and heat over medium. When hot, scoop about 1/4 cup of batter for each pancake. You'll need 24 pancakes total (two for each slider). Cook until bubbles form on the surface, about 2-3 minutes, then flip and cook another 1-2 minutes. Keep warm in a 200°F oven if needed.
Prepare the maple butter glaze: In a small saucepan, melt the butter over low heat. Stir in the maple syrup and a pinch of salt. Simmer for 1-2 minutes until slightly thickened, then remove from heat.
Assemble the sliders: Place a sausage patty on a pancake, add any optional ingredients (cheese, egg, etc.), then top with another pancake. Repeat with remaining ingredients.
Glaze and serve: Drizzle the warm maple butter glaze over the assembled sliders. For extra presentation points, stick a toothpick through each slider to hold them together and make them easier to grab.
Serve immediately while warm and gloriously sticky.