Roast ground almonds in a dry pan over medium heat until golden brown, stirring occasionally. Let cool.

In a large bowl, combine roasted almonds, flour, cinnamon, sugar, butter, and egg.

Knead the mixture until a soft, slightly sticky dough forms. Add more flour if too sticky.

Shape the dough into a ball, wrap in plastic wrap, and refrigerate for 2 hours.

On a lightly floured surface, roll out the dough to about 0.5cm (1/5 inch) thickness.

Cut out circles to fit your tartelette pans using a bowl or cookie cutter.

Line the molds of the tartelette pan with the dough circles.

Spoon 2-3 tablespoons of jam into each mold, being careful not to overfill.

Use remaining dough to cut out small circles or strips for the top of the tartelettes.

Arrange the cutouts on top of the jam in decorative patterns.

Bake in a preheated oven at 190°C/375°F for 20 minutes, or until golden brown.

Check after 15 minutes to prevent burning. Let cool before serving.