In a medium sized bowl, combine flour, brown sugar and cinnamon together. Cut in butter with a pastry blender or your hands until mixture becomes crumbly. Set aside.
Cake
Preheat oven to 350 degrees.
Spray 8-inch springform pan or round cake pan with cooking spray.
In a medium-sized bowl, whisk flour, baking powder, baking soda and salt.
Using a stand or hand mixer, combine powdered sugar and butter together. Add vanilla and egg. Add milk and lemon juice; beat for 2 minutes.
Add flour mixture to sugar mixture, and stir until smooth.
Spoon half of batter into prepared pan, spreading evenly. top with strawberry jam. Spoon remaining batter over strawberry layer. Sprinkle with crumb topping.
Bake for 45 minutes or until a toothpick inserted into center comes out clean. Cool for 10 minutes before removing sides from springform pan. Cool completely on wire rack.
Notes
I used Raspberry Jam for this cake. I guess, you can even use mixed fruit jam or mixed berry jam for this cake. Also, if you prefer a less sugary cake, cut the amount of jam to 3/4 cup instead of 1 cup. I used a regular baking tin. Make sure you line the sides of the baking tin too, with parchment / baking paper. Jam tends to caramelise while baking and sticks to the side. Please be careful, while removing the cake from the tin. Make sure, you loosen the sides of the cake first with a tooth pick or a knife and then remove the cake.The cake can be stored at room temp for 2-3 days, in an airtight container. Make sure the cake cools completely, before storing, otherwise the topping may become mushy.