In a large bowl, whisk together the flour, baking powder, salt, and brown sugar.
In a medium bowl, combine milk, yogurt, eggs, maple syrup, melted butter, and vanilla extract. Whisk until combined.
Pour wet ingredients over dry ingredients and stir until combined.
Heat a griddle or pan to medium low heat. Coat with cooking spray. Spray the inside of a heart shaped cookie cutter with cooking spray. Place the cookie cutter on the griddle or pan and fill with about 1/4 cup of pancake batter. Cook until surface of pancakes have some bubbles and a few have burst, 1 to 2 minutes. Remove cookie cutter and flip carefully with a spatula. Cook until browned on the underside, 1 to 2 minutes more. Continue making pancakes until the batter is gone.
Serve pancakes warm with strawberries, butter, and maple syrup, if desired.
Note-If you don't have a heart shaped cookie cutter, you can pour or pipe the pancake batter into heart shapes. It's ok if they aren't perfect. These pancakes freeze well. Let them cool completely and then wrap in plastic wrap and put in a freezer bag. When ready to eat, remove from freezer and reheat in microwave or the toaster.