Preheat your oven to 450°F (232°C).
In a mixing bowl, combine 2 cups of self-rising flour, baking powder, butter, yogurt, and milk. For tender biscuits, handle the dough as minimally as possible and keep the ingredients cold. For best results, freeze the butter in advance. Stir with a spoon rather than a mixer to maintain a light texture.
The dough will appear shaggy. Lightly dust a cutting board with the remaining ¼ cup of flour. Pat the dough into a ½-inch thick rectangle. Fold the dough in half, then pat it down to ½-inch thickness again. Repeat this folding and patting process five times to create flaky layers. The final rectangle should be approximately ¾-inch thick.
Use a biscuit cutter, glass, or knife to cut the dough into 8 rectangles or rounds. Avoid twisting the cutter, as twisting seals the edges and prevents proper rising.
Arrange the biscuits on a greased cast-iron skillet or baking sheet, leaving about 1 inch of space between them. Spray the tops with cooking spray.
Bake for 10–12 minutes, checking for doneness around 8 minutes. Remove from the oven when the biscuits are golden brown.