Whisk the all purpose flour, whole-wheat flour, cream of tartar, baking soda and salt in a medium bowl.

Whisk the eggs, buttermilk and sugar in a large bowl until foamy, then stir in melted butter. Add flour mixture and stir until just combined. (The batter will be thick; it's ok if there are a few lumps).

Heat a large skillet over medium-low heat until hot. Lightly brush with vegetable oil. Drop a heaping 1/4 cupful of batter into the skillet for each pancake and spread into a 4 - 5 inch round with the back of a spoon. Cook until the bubbles on top burst and the edges begin browning, about 4 minutes. Flip and cook until golden brown, 2 - 3 more minutes.serve with butter and syrup.