In a bowl, combine cake mix, one egg, oil and 1 teaspoon lemon zest until crumbly. Set aside 1 cup for topping. Press the remaining crumb mixture into a greased 13 x 9 x 2 baking dish. Bake at 350º for 15 minutes or until golden brown. Remove from oven, cool crust 10 minutes.
In a small bowl, beat cream cheese until fluffy. Beat in the sugar, lemon juice, remaining egg and 1 teaspoon lemon zest until smooth. Spread over crust. Sprinkle with reserved crumbs.
Bake for 20 to 25 minutes or until golden brown. Cool on wire rack.