butter tart squares

From April 2008's Canadian Home & Country magazine, which I love:

Butter Tart Squares

1/2 cup unsalted butter, softened
2 tbsp granulated sugar
1 1/2 cups all-purpose flour
1 1/2 cups brown sugar, packed
2 eggs
1/4 cup unsalted butter, melted
1 tbsp lemon juice
1 tsp vanilla
1/2 cup toasted, chopped walnuts
1/2 cup golden raisins

Preheat oven to 350. Cream butter and sugar. Stir in flour to make a soft dough. Press into 9x9 pan and bake for 10-12 minutes (dough will still be pale).
In a large bowl, beat together brown sugar, eggs, melted butter, lemon juice, and vanilla. Stir in walnuts and raisins. Pour filling over par-baked crust, spreading evenly. Bake for 30-35 minutes, or until filling begins to bubble and carmelize. Allow to cool before cutting into squares.

Prepare to a)eat the entire pan or b)have people over to help polish the squares off. They're amazing.