• Preheat oven to 350 degrees. Prepare a 9 x 9 inch baking dish by lining it with parchment paper.
• Be sure to leave the parchment paper long enough so that it hangs over the pan a little - enough to grab - this will help ease the removal of the cake from the pan.

CREAM CHEESE LAYER

• In a bowl, use a handheld mixer to blend together the cream cheese, sugar, egg, and lemon juice until well combined and creamy. Set aside.

CAKE LAYER

• In bowl, use a whisk to mix together the all purpose flour, baking powder, baking soda, and salt. Set this aside as well.
• Next, in a clean bowl, use a handheld mixer to blend the vegetable oil and sugar. Mix well; at least two full minutes. Then, add the egg and incorporate into the oil and sugar mixture.
• Add the yogurt, lemon zest and juice. Blend until well mixed - at least 3 full minutes on medium speed.
• To the sugar and oil mixture, add the flour mixture. Use the handheld mixture to blend the two together on low speed. Just mix until combined - do not over mix the batter.
• Pour the batter into the baking dish and smooth it evenly around the dish. Be sure to get into the corners.
• Now, spoon the cream cheese mixture onto the top of the cake batter base. Carefully spread it - do not mix the cream cheese into the batter.

CRUMB TOPPING LAYER

• Add the crumb topping ingredients to a small bowl. Use a fork to smash the butter into the flour and sugar to form a crumbly paste.
• Sprinkle the crumb mixture evenly over the cream cheese layer.
• Bake for 45 minutes. Remove from oven and allow to cool for five minutes before removing from pan. Allow to finish cooling on a wire cooling rack. Cut into 16 squares.