Preheat the oven to 375F.

In a medium bowl, whisk together the dry ingredients. In a separate bowl, mix the wet ingredients until well combined.

Gradually add the wet ingredients to the dry ingredients, stirring with a spatula until fully incorporated.

Divide the dough in half. Place each half between two sheets of parchment paper on the countertop. Using a rolling pin, roll the dough into a ⅛-inch thick rectangle.

Transfer the parchment-covered dough to a baking sheet for support, then refrigerate for 20 minutes.

Remove the dough from the refrigerator and let it come to room temperature, about 20 minutes.

Line two baking sheets with the top sheets of parchment paper from the rolled-out dough.

Using a 3-inch round cutter or a 3-inch upside-down glass, cut out circles from the dough.

Carefully transfer the rounds to the lined baking sheets. If needed, use a rubber spatula to lift them without tearing.

Place 2 teaspoons of jam in the center of each round. Gently fold the edges to form a triangle, pinching firmly at the top and each bottom corner. This dough can be delicate, so handle it with patience. If it cracks or crumbles, pinch it back together firmly, ensuring a tight seal on all three edges to prevent the jam from leaking out during baking. Arrange the hamantaschen 2 inches apart on the baking sheet.

Bake for 10-12 minutes, or until lightly golden. Let them cool on the baking sheet for at least 10 minutes before transferring. Serve immediately or store in an airtight container at room temperature for one day, or in the refrigerator for up to three days.