Step 1

First, make your dough.

Step 2

Whisk together the flour, sugar, and salt in a large bowl or the bowl of your food processor. Add in the chopped pieces of cold butter and cold shortening.

Step 3

Blend together with your hands or pulse with your processor until you have coarse crumbs.

Step 4

Mix together the water and vinegar in a small bowl. When ready, slowly drizzle it over the dough, a tablespoon or so at a time, gently stirring the mixture with a fork or pulsing with your processor, until fully incorporated (you may not use all of the water).

Step 5

It might seem a bit too wet at this point, but it will dry up while it sits in the fridge. Form the dough gently into 2 loose balls, wrap tightly in plastic wrap, and chill in the fridge for a minimum of 3 hours or as long as overnight.

Step 6

Make your filling when you are almost ready to use your dough.

Step 7

When you're ready to bake, liberally butter your muffin tins.

Step 8

This recipe makes about 30-36 tarts.

Step 9

Preheat your oven to 400 degrees F.

Step 10

Lightly flour a work surface, and take one of your balls of dough and roll it out to about ¼-inch thick.

Step 11

Cut out circles that are a bit larger than the circumference of your tins, so that there is enough crust to hold in the filling, and gently place each circle in the tins, re-rolling your dough as you go.

Step 12

Drop 3-4 raisins in the bottom of each tart before adding in the filling.

Step 13

Whisk together your dark brown sugar, corn syrup, melted butter, and vanilla. Drop 2-3 teaspoons of filling (it will bubble during baking so don't overfill ) then sprinkle with a touch of sea salt.

Step 14

Bake for 12-15 minutes, until lightly golden and mostly set.

Step 15

Allow to cool completely before removing the tarts from the pan. I used a dull paring knife to cut around any hardened caramel and then popping each tart out.

Step 16

These will keep well at room temperature for up to 3 days, or frozen for up to 3 months.