In a medium bowl, blend together the softened butter, 2 cups flour and 1/2 cup sugar. Press into whatever shallow pan (ungreased!) you have. 9" works great!
Bake for 15 to 20 minutes in the preheated oven, or until firm and golden.
In another bowl, whisk together the remaining 1/4 cup sugar and 3 tbls flour. Whisk in the eggs, lemon juice. and the blended 1/4 cup of frozen raspberries. Pour over the baked crust (it's fine if it's warm).
Bake for an additional 20 minutes in the preheated oven. Keep an eye if the liquid is starting to firm up. Take it out and let it cool.