Place the flour, salt, Dutch-Processed cocoa, and sugar in the bowl of a food processor (see notes). Run the food processor for about 10 seconds to combine the ingredients.

Cut the butter into cubes and place in the food processor. Pulse until the butter has broken up and no large chucks are visible. Don't over processes.

In a separate bowl whisk together the egg and heavy cream. While the food processor is running slowly add the egg/heavy cream mixture. As soon as the dough forms a ball stop the food processor.

Scoop the dough out onto a well floured work surface and kneed gently just until it comes together and forms a ball. Wrap in plastic wrap and put in the refrigerator for at least an hour before rolling. You can also store overnight.

When ready to roll preheat the oven to 350°F.

Take the dough out of the refrigerator and roll between the parchment until you get a square (or round depending on the shape of your tart pan) large enough to cover the bottom and sides of the pan. Make sure your parchment sheets are large enough to roll to 11-12 inches in each direction.

Lay the dough in the tart pan and press it down into the pan and up the sides. Trim the dough flush with the top edge, then prick all over the bottom with a fork.

Bake at 350°F for 18-20 minutes or until firm. Cool completely before adding filling

Place the chocolate chips in a heat proof bowl, set aside

Put the heavy cream into a microwave safe measuring cup or bowl and microwave for 2-3 minutes or until boiling. If you don't have a microwave you can bring to a boil in a saucepan on the stove.

Pour the hot cream over the chocolate and let it sit for about 5 minutes so that the chocolate melts

Using a whisk slowly stir the chocolate until it has completely mixed with the cream. If there are any lumps of un-melted chocolate you can microwave for a few seconds (no more than 10 seconds at a time) to melt it completely.

Stir in the corn syrup and 0.5-1 teaspoons of extract of your choice. Allow to cool before pouring into tart shell.

Combine the heavy cream and mascarpone in the bowl of a stand mixer (or a stainless steel bowl if using an electric hand mixer). Mix by hand until well combined (you want to get them combined by hand before using the electric mixer).

Add the sugar and vanilla extract to the bowl, then beat on high speed until stiff peaks form.

Refrigerate until ready to use. Any unused portion can be refrigerated in an air-tight container for 1-2 days

Once the tart shell has cooled pour in the chocolate ganache and smooth with a spatula.

Place the mascarpone whipped cream in a pastry bag fitted with a shell piping tip. Pipe the mascarpone whipped cream to look like the lines of a flag. If you don't have a pastry bag you can put it into a zipper top bag and cut a corner off to pipe straight lines of whipped cream to make it look like the stripes of a flag (see notes)

Once the top is covered in with whipped cream add the washed and dried blueberries and raspberries (or strawberries) to look like an American flag.