Preheat the Oven: Set your oven to 350°F (175°C). Line a baking sheet with parchment paper.

Make the Dough: In a food processor, combine the flour, salt, garlic powder, and cold butter cubes. Pulse until the mixture resembles coarse crumbs.

Add the Cheese: Add shredded cheddar and pulse again until the dough starts to come together. It should be crumbly but hold when pressed.

Shape the Dough: Scoop about a tablespoon of dough and roll into balls. Place on the prepared baking sheet about 1 inch apart.

Create Thumbprints: Using your thumb or the back of a small spoon, gently press a shallow indentation in the center of each dough ball.

Bake the Shells: Bake for 10–12 minutes, until the edges are lightly golden and the centers are set. Remove from the oven.

Add the Filling: Spoon about ½ teaspoon of onion bacon jam into each indentation.

Finish Baking: Return to the oven for another 3–4 minutes, just to warm the jam slightly and meld the flavors.

Cool and Serve: Allow to cool for a few minutes before serving. Enjoy warm or at room temperature.