Preheat your oven to 350°F and line an 8×8 square baking dish with parchment paper.

In a mixing bowl, combine the brown sugar, flour, baking soda, salt, and oats.

Stir or use your hands to incorporate the softened butter until the mixture becomes crumbly.

Press two cups of the mixture into the bottom of the prepared baking dish.

Evenly spread the raspberry jam over the crust, leaving about ¼ inch from the edges.

Sprinkle the remaining crumb mixture over the jam layer and lightly press it down.

Bake for 30-40 minutes or until the top is lightly browned.

Allow the bars to cool before cutting them into squares and serving.