Preheat the oven to 350F.

Lightly coat 2 (9-inch) round cake pans or a 9x13-inch baking pan with spray oil.

In a large bowl, whisk together pastry flour, lemon zest, baking powder, baking soda and 1 teaspoon of the salt until well combined.

In a medium bowl, combine diced strawberries and 1 cup of the brown sugar.

Using the back of a fork, mash until strawberries are juicy.

Add lemon juice, eggs, oil and sour cream and stir until blended.

Fold strawberry mixture into flour mixture and gently stir until no streaks of flour are visible.

Pour batter into the prepared baking pan(s).

In a small bowl, combine butter, all-purpose flour, remaining 1/4 cup brown sugar and remaining 1/2 teaspoon salt.

Using the back of a fork, lightly mash until crumbly.

Sprinkle topping over cake(s).

Arrange sliced strawberries on top, gently pushing them down.

Bake until a toothpick inserted into center of cakes comes out with moist crumbs, 40 to 45 minutes.

Cool completely on a wire rack before slicing.