01 - Preheat your heart-shaped waffle iron according to the manufacturer's instructions. Lightly grease with melted butter or nonstick spray.
02 - In a large bowl, whisk together flour, sugar, baking powder, and salt until well incorporated.
03 - In a separate bowl, beat the eggs, then add milk, melted butter, and vanilla extract. Whisk until smooth.
04 - Pour the wet ingredients into the dry ingredients. Stir gently until just combined; do not overmix as a few lumps are acceptable.
05 - Pour approximately 1/2 cup batter onto the preheated waffle iron. Close and cook until golden and crisp, 3 to 5 minutes per batch.
06 - Remove cooked waffles and keep warm in a low-temperature oven. Repeat with remaining batter until all waffles are prepared.
07 - Arrange waffles on serving plates. Top with mixed berries, dust with powdered sugar, and drizzle with maple syrup or honey if desired. Garnish with fresh mint leaves.