Combine the butter and sugar in a large bowl. Using a sturdy spatula or Danish whisk, beat until creamy. Add vanilla and salt and mix until combined. Add the all-purpose and almond flours and continue to mix until flour is incorporated and large crumbles start to form.

Spray a 9 or 10-inch tart pan with baking spray or grease well and press one half of the dough evenly into the pan to form a bottom crust. Wrap the remaining dough in plastic wrap and freeze while the bottom crust is baking, (no longer than 15 minutes).

Place the tart pan on a baking sheet and bake for 10-12 minutes, until the crust is just beginning to firm and turn pale golden brown at the edges.

Remove the pan from the oven and allow the tart to cool for 10 minutes, then spread the raspberry jam/preserves evenly over the crust, leaving a ¼-inch border around the edge. (see notes above for a pretty presentation tip).

Return the pan to the oven and continue baking until topping is firm, crisp and lightly golden in color, about 25-30 minutes. Transfer to a wire rack and let cool to room temperature, then dust lightly with powdered sugar, if desired.

Use a sharp knife to cut the tart into wedges. Serve warm (I used the microwave for about 10 seconds for each wedge) with a scoop of vanilla ice cream or frozen custard, if desired.