Mix ingredients separately: Place all dry ingredients in a large bowl and mix well. Beat egg whites in a medium measuring jug until stiff peaks form. Blend wet ingredients in a large measuring jug until smooth.
Combine egg whites and wet ingredients: Fold egg whites through wet ingredients using a rubber spatula.
Combine wet and dry: Pour wet ingredients into dry ingredients and mix until JUST combined. Do NOT overmix! Lumps are fine. Rest batter for 20-30 minutes before cooking.
Cook pancakes: Heat griddle or skillet over medium-high heat (I heat mine to 400-420°F).Using a heaping ¼ per pancake, cook until bubbles appearing on surface pop, flip and cook until done. Repeat until all batter has been used.
Serve pancakes immediately, or keep warm on a rack at 100°F in the oven.
Notes
Ingredient notes
Don't want to use white flour? You can use half whole wheat, all whole wheat or all white flour for these pancakes - I have tried all versions multiple times, and they're all delicious. When using 100% whole wheat flour, you may need to add an extra splash of buttermilk.
Don't have buttermilk? Just stir 1 tablespoon vinegar (white or apple cider is best) into regular milk and let it sit on the counter for 5-10 minutes before using it. An easy substitute! You can also use 1 ½ cups milk and ½ cup Greek yogurt - which is a favorite of mine. The yogurt works really well even when using buttermilk in combination with it and yields even thicker pancakes in my experience.
No time to separate the eggs? Just skip this step and whisk the whole eggs until frothy before adding the remaining liquid ingredients.
Oil: I strongly recommend using a neutral vegetable oil, you do not want an oil with a strong taste. For extra-delicious pancakes, use melted butter instead!
Recipe tips
DO NOT overmix! Really, this is THE most important thing when making pancakes. Lumps are ABSOLUTELY fine. I usually don't stir more than 10-15 times when I make pancake batter. This is how you get the fluffiest pancakes!
Make sure to allow the batter to rest for 20-30 minutes before cooking, otherwise the buttermilk can't do its job and the pancakes won't be as fluffy as you want them to be.
I highly recommend cooking a single test pancake first, that way you can gauge if you need to increase or decrease the temperature, if the batter needs a little tweaking (a splash more buttermilk if the pancakes come out too thick, a couple of tablespoons of flour if the batter is too runny and the pancakes too flat; more salt and vanilla if they need more flavor).
I very strongly recommend to cook these over medium-high heat. I know many cooks feel strongly about cooking pancakes over low heat for a longer period of time, but I have tested the cooking temperature for this recipe extensively, and nothing below 400°F yields good pancakes. The batter needs heat in order to rise and set into fluffy pancakes. Lower heat yields gummy pancakes that collapse into dense cakes shortly after taking them off the griddle.
Freezer tips
Freeze cooled pancakes in labelled freezer bags for up to 3 months.
No need to defrost when reheating - reheat in bursts in the microwave, in a toaster oven or in the toaster.