Preheat oven to 350. Lightly grease a 9x13" baking dish and set aside.

In a large mixing bowl, whisk together the flour, salt, baking powder, sugar, and citrus zest. Set aside.

Using a cheese grater, grate 1 cold stick of butter. Lightly toss the butter with flour mixture until it's mixed evenly and crumbly (don't over-mix here). Whisk the eggs and then lightly toss them with the flour/butter mixture until evenly absorbed. Add in the cream and mix until combined; the mixture should be quite sticky and a little lumpy (kind of like biscuit dough). Lightly press about 1 1/2 cups of the dough mixture into the bottom of the prepared pan and set it aside.

Toss the berries with the brown sugar and spread it over the prepared "crust." Drop the remaining dough over the berries and set aside.

Whisk together the sugar, flour, and cinnamon for the streusel topping. Cut in the butter until the mixture is crumbly. Sprinkle over the dough and bake for 45-55 minutes or until the top is golden brown and the crust is cooked through. Serve warm with sweetened whipped cream or vanilla ice cream.