In the bowl of an electric mixer fitted with the paddle attachment, cream together the butter and sugar for about 5 minutes. Add in the egg and vanilla and mix until incorporated. Add in the flour and salt on low speed and mix until just incorporated.

Scrape the dough out onto a piece of plastic wrap and shape into a disk. Wrap and refrigerate for at least 1 hour or overnight.

Flour work surface and roll out your dough to 1/4" thick. Press the dough into the bottom and up the sides four 4″ tartlet pans. Place in the freezer for 10-15 minutes, or in the fridge for an hour.

When ready to bake, preheat the oven to 350°F. Line your crust-filled tart shell(s) with tin foil, and fill with pie weights or dried beans. Bake for 20 minutes. Remove the foil and weights from the tarts and bake for about 10 minutes more, or until the tart shells are golden. Let cool on a wire rack before filling.

In a small saucepan, combine all of the ingredients, and bring to a boil over medium-high heat.

Continue to cook for about 5 minutes, until thickened.

Allow to cool for 5 minutes, then divide into the four tartlet shells. Place in the fridge to chill.

In a small bowl, stir together the sour cream, brown sugar, and vanilla, until smooth.

Dollop onto the chilled tarts, and top with a mini strawberry.

Serve!