Preheat the oven to 325˚F. Spray two 12-cup mini muffin pans (or one 24-cup mini muffin pan) with baking spray. Rub each cup with a piece of paper toweling to make sure they’re thoroughly coated, including the top edges.

Place the soft butter and powdered sugar in a medium-size bowl and stir until smooth and creamy. Add the vanilla and stir to combine. Sprinkle in the corn starch and stir until nice and smooth.

Add the flour and salt and stir, turning the bowl and stirring from the bottom up. At first, the dough will be very shaggy and dry, but after a minute or so it will come together nicely. Just keep stirring until all of the flour is incorporated and the dough comes together in a big clump.

Divide the dough into 24 equal portions. You can eyeball this or use a scale. I weigh the dough and then divide it by 24. It usually comes out to 25-26g each. Give each portion of dough a little squeeze and hold it in your hand for about 10 seconds (to compress and warm the dough a bit) then roll it between your palms into round balls.

Place each ball into one of the prepared mini muffin cups and flatten each one gently with your fingers. Using a ½ teaspoon measuring spoon (see the pictures above in the post), make an indention in the center of each flattened ball. (I like to do about 3 at a time: squeeze 3 portions, roll them into balls then make the wells. This keeps the dough from drying out and cracking when you make the little wells.) If the dough cracks at the edges, just push it together with your fingers while the spoon is still in the center.

Place the pan(s) in the preheated oven and bake for 10 minutes then remove the pan from the oven and reinforce the wells again with a half teaspoon measuring spoon. Bake for another 8-12 minutes or until the outer edges of each tart are a medium golden brown. Remove from the oven and immediately reinforce the center wells one last time, by pushing in with the ½ teaspoon measuring spoon. You can make the wells as shallow or deep as you’d like at this point.

Allow the tart shells to cool in the pan for 10 minutes then remove them from the pan by inserting a small sharp knife into the center of each shell and pulling upward. Cool completely on a cooling rack before filling.

Unwrap the caramels and place them in a small saucepan. Add the cream or half and half. Heat over medium-low heat until the caramels are melted. Stir well to create a creamy sauce. Leave the caramel sauce on the burner with the lowest heat beneath it to keep it nice and spoonable. Spoon the sauce into the tart shells, filling to the top of the well. Sprinkle with flaky sea salt and allow the shortbread bites to cool completely.