Preheat the oven to 350F. Line an 8×8 inch square baking pan with parchment paper or spray the baking dish with non-stick cooking spray.

In a large bowl or in the bowl of a stand mixer fitted with a paddle attachment beat together the flour, brown sugar, salt, 2 teaspoons lemon zest and butter on medium speed, until a crumbly dough forms(not a smooth cookie dough). Alternately beat the mixture with a handheld electric mixer.

Press 2/3 of the dough in an even layer into the bottom of the prepared pan.

In a small bowl mix raspberry jam with 1 teaspoon of lemon zest. Then spread the raspberry jam over the bottom crust, top with fresh raspberries.

Crumble the remaining dough over the raspberry mixture.

Bake the bars for 45-50 minutes or until the crumble topping is golden brown and the jam is bubbly.

Remove from the pan from the oven and let the raspberry crumble bars cool on a wire rack to room temperature. Make sure that you cool the bars otherwise they will fall apart.

Cut the bars with a sharp knife and serve.