Whisk together flour, baking powder, baking soda, and salt in a large bowl.
In a medium bowl, whisk together yogurt, milk, eggs, and oil.
Whisk wet ingredients into flour mixture until just combined. (Batter will be a bit lumpy.)
For Pancakes: Heat a large non-stick pan over medium-low heat. Spray pan with nonstick cooking spray, or add a small amount of oil to pan. Pour about ½ cup batter onto pan for each pancake. Cook each side for about 2 minutes. Flip and cook remaining side for an additional 2 minutes. Repeat process until all batter is cooked.
For Waffles: Use a waffle iron, treated with cooking spray or oil to prevent sticking. Pour about ⅓ cup per waffle. Cook for about 3½ minutes.