In a medium bowl, whisk together egg yolks, milk, and vanilla extract until smooth. Sift in flour and baking powder, and gently fold until just incorporated.

In a separate bowl, beat egg whites until foamy. Gradually add sugar and cream of tartar (if using), then beat until stiff peaks form.

Fold one-third of the egg whites into the batter to lighten it, then fold in the remaining egg whites until no streaks remain.

Preheat a non-stick skillet over low heat and grease with butter. Scoop batter into the pan, cover, and cook for 4-5 minutes until golden brown.

Carefully flip the pancakes, cover again, and cook for another 4-5 minutes until cooked through.

Stack the pancakes on a plate, dust with powdered sugar, garnish with fresh fruit, and drizzle with maple syrup.