Preheat oven to 350°F (175°C). Line an 8x8-inch baking pan with parchment paper.

In a large bowl, mix flour, granulated sugar, brown sugar, and salt. Cut in the butter using a pastry cutter or your hands until the mixture resembles coarse crumbs.

Press half of the mixture firmly into the prepared pan to form the crust.

Spread the jam evenly over the crust, leaving a small border around the edges.

Crumble the remaining mixture over the jam layer.

Bake for 30-35 minutes, or until the top is golden brown.

Let the bars cool completely in the pan before slicing into squares.

Alternate Instructions:

Combine flour, sugars, and salt in a bowl. Mix in cold butter until crumbly.

Press half into a pan, add jam, and top with crumbles.

Bake until golden, then cool before slicing.