I used to have a nifty little tool that supposedly helped cut the butter into the dry ingredients, but it never worked well for me. Nor did using two criss-crossing knives. I got to where I would cut the cold butter into very small cubes, and I would then use my hands to rub the butter into the flour. This is messy and time-consuming, and the butter gets too soft, which makes the dough not bake up as fluffy.
I learned a new trick this week. It may be old hat to you, but somebody else might like it as much as I did. Simply grate the cold butter into your dry ingredients with a cheese grater. It's that simple. Makes your baked goods turn out perfectly fluffy.
My favorite biscuit recipe:
2 cups flour - I use 100% whole wheat pastry flour, and they don't come out dry at all
1/2 cup (1 stick) butter
1 tsp salt
1 tbsp baking powder
yogurt, buttermilk, cream, or milk
Mix together dry ingredients. Grate butter into mixture, and stir with wooden spoon until evenly distributed. Add enough yogurt (or other liquid) to make a smooth dough, and knead by hand about 15 times. Roll dough to 1/2 inch thickness, cut out biscuits, and bake at 425 degrees for about 8-10 minutes. Enjoy!