White cake with lemon filling and lemon butter frosting.
This is the best white cake recipe that i've found so far, and so i use this recipe for other cakes not just with the lemon filling and frosting.

2 cups all-purpose flour
2 teaspoons baking powder
1 teaspoon salt
1/2 cup butter
1 1/4 cups white sugar
3 egg replacer (powdered for the most "white cake" result)
1 teaspoon vanilla extract
1 cup soy creamer (soy milk would suffice)

filling:
1 tablespoon grated lemon zest
1/2 cup fresh lemon juice
1 tablespoon cornstarch
6 tablespoons butter
3/4 cups sugar
4 egg replacer (or 1 cup applesauce)

frosting:
4 cups powdered sugar
1/4 cup butter
1/4 cup shortening
2 tablespoons fresh lemon juice
2 tablespoons soy milk

preheat oven to 350 degress F, grease and flour 2 8" round pans. In a large bowl, cream together butter and sugar until light and fluffy (about 5 minutes) beat in the egg replacer, and then vanilla. beat in flour, baking powder and salt. Beat in the milk until just incorporated.

Pour batter into prepared pans. Bake in the preheated oven for 30 minutes, or until a tooth pick inserted comes out clean. Cool on wire racks in pan for 10 minutes, and then invert onto wire racks to cool completely.

To make filling: in medium saucepan, mix together 1 tablespoon lemon zest, 1/2 cup lemon juice and 1 tablespoon cornstarch until smooth. Mix in 6 tablespoons of butter and 3/4 cup sugar, and bring mixture to a boil over meduim heat. Boil for one minute, stirring constantly. in a small bowl with a wire whisk beat egg replacer until smooth, whisk a small amount of the hot lemon mixture. pour the egg mixture into the saucepan, reduce heat to low, cook 5 minutes until thick (do not boil).

spread the lemon filling on the top of one of the cakes, top with remaining cake and frost.