I like to use a combination of the two. Buttermilk gives these waffles the best flavor, while milk helps produce a lighter texture. The purpose of buttermilk in most recipes, including waffles, is to add acid to the reaction with baking soda to make it “rise” higher. The thickness helps the dough retain the air pockets that acid and baking soda create when heat is applied, resulting in a “lighter and fluffier” waffle.
Buttermilk waffles have a slightly bitter and unique flavor that differentiates them from other milk-based waffles. Known for their spongy texture that is considerably more elastic and airy than homemade waffles, butter waffles are prepared with flour, salt, sugar, baking soda, vegetable oil and buttermilk. The acid in buttermilk, which is normally fermented with baking soda instead of baking powder, reacts quickly with baking soda and neutralizes its otherwise metallic flavor to create light but crunchy waffles. Buttermilk is also a complicated ingredient because it tends to make a heavier dough, resulting in waffles that are less crispy.
These types of waffles are characterized by their crisp exterior and are generally thinner than their buttermilk counterparts, although they still contain a light and airy center when done right. Serve buttermilk and homemade waffles with syrup or fruit butter for a delicious and filling treat.