This recipe comes from The Joy of Cooking. It is so simple to make and deliciously buttery. It is also very versatile - you can spread raspberry jam and crumb topping on top to make raspberry bars, or add lemon zest to the dough then drizzle a lemon glaze on top for lemon bars.
Preheat oven to 325 degrees.
1 Cup Butter (at room temperature)
2 Cups sifted all-purpose Flour
1/2 Cup Powdered Sugar
1/4 teaspoon salt
Cream the butter until soft. Sift together the Flour, Sugar, Salt. Add the flour mixture to the butter just until well combined. It will be crumbly. Pat into a 9x9 pan and press down. Pierce with a fork through the dough in several places. Bake 25-30 minutes. Cut into squares while warm.