Prep the pan and oven: Preheat the oven to 350°F (175°C). Line an 8x8-inch baking pan with parchment paper, leaving an overhang on two sides for easy lifting.

Make the raspberry filling: In a small saucepan, add 2 cups raspberries (fresh or frozen), 3–4 tablespoons powdered sweetener, 1 tablespoon lemon juice, and a pinch of lemon zest. Cook over medium heat, stirring and mashing, until the berries break down and thicken, about 5–7 minutes.

Thicken with chia: Remove from heat and stir in 1–1.5 tablespoons chia seeds. Let it sit 10 minutes to gel. Taste and adjust sweetness or lemon if needed. Set aside to cool slightly.

Mix the crust: In a bowl, whisk together 2 cups almond flour, 2 tablespoons coconut flour, 1/3–1/2 cup powdered sweetener, 1/2 teaspoon baking powder, and 1/4 teaspoon salt.

Add wet ingredients: Melt 1/2 cup (1 stick) unsalted butter and let it cool slightly. Stir in 1 teaspoon vanilla. Pour into the dry ingredients. If you want a sturdier crust, beat in 1 egg as well. Mix until the dough looks like moist crumbs that clump when pressed.

Press the base: Transfer about 2/3 of the dough to the lined pan. Press firmly into an even layer using your fingertips or the bottom of a measuring cup. Prick a few holes with a fork.

Par-bake: Bake the crust for 10–12 minutes until just set and slightly golden at the edges. Let cool 5 minutes.

Assemble: Spread the raspberry chia jam evenly over the warm crust. Crumble the remaining dough over the top in small clusters. For extra texture, sprinkle a tablespoon of sliced almonds if you like.

Bake: Return to the oven and bake another 18–22 minutes until the top is lightly golden and the filling looks set at the edges.

Cool completely: Let the pan cool on a rack. Then chill in the fridge for at least 1–2 hours before slicing. This step helps the bars set and cut cleanly.

Slice and serve: Lift the bars out with the parchment overhang and cut into 12–16 squares. Enjoy at room temperature or chilled.