combine the flour, brown sugar, cinnamon, and salt.
cut in the butter, until you have pea-sized bits of butter mixed throughout the flour.
Pancakes
heat a griddle or skillet over medium-low heat. grease your skillet or griddle with butter.
combine the flour, sugar, baking powder, cinnamon, and salt in a mixing bowl.
whisk together the milk, eggs, butter, and vanilla in another bowl.
add wet ingredients to the dry and stir just until combined - batter will still be lumpy.
for each pancake place 2 tsp of streusel on griddle, top with 1/4 cup of pancake batter. add diced apple and another 2 tsp of streusel on top of batter.
cook until tiny bubbles appear on the pancake, and the edges begin to dry (about 4 minutes). flip and continue cooking until the pancakes are cooked all the way through (3-4 more minutes).
repeat with the remaining batter. pancakes can be kept warm in a 200-degree oven until you are ready to serve.