Cut the butter and shortening into cubes. Freeze 30 minutes beforehand.
In the bowl of your food processor with the regular blade attached, add flour. Add butter and pulse. Add shortening and pulse. The butter and shortening need to be very cold.
Add salt and pulse 3 times for 3 counts each time.
With the processor running, pour cold red wine into the bowl. Process just until the dough begins to get crumbly. Do not wait until it's a big clump. It will be way too moist at that point and will be tough.
Stop the processor and dump the dough onto a sheet of plastic wrap. Using your hands, press the dough into a ball squeezing if necessary to make it stick together.
Wrap the dough in plastic wrap and chill it about 30 minutes in the refrigerator. Roll it out on a cool surface if possible (This will prevent the fat from melting.) Press into a 11-inch tart pan. Or, if you're not ready to fill it with the tart ingredients yet, refrigerate the crust until you get them ready.
CANDIED WALNUTS
In a 12-inch skillet, bring nuts, sugar, and water to a boil.
Reduce heat to a low boil and cook stirring until syrup mixture has caramelized and the nuts are well coated. This will take 8 to 10 minutes.
Immediately spread nuts on a sheet pan lined with parchment paper and spread into a single layer.
Bake in a 300°F oven for 10 minutes. Stir and bake for an additional 8 minutes.
Remove from oven, stir and allow to cool.
TART
Preheat oven to 375°F.
Roll out the pastry dough into an 11-inch tart pan. Cut off the extra around the edges. Poke the pastry with a fork to create small holes. Bake pastry crust 7 to 8 minutes at 375° or until it starts to brown. Remove from the oven.
Slice or crumble cheese and evenly spread it over the crust. Spread halved grapes randomly over cheese. Spread walnuts over cheese.
Bake 20 to 25 minutes or until cheese is melted and pastry edges are browned.
Remove from oven and cool 5 to 10 minutes. Before serving drizzle balsamic reduction and mint or basil over tart.
Refrigerate leftovers in an airtight container. The tart can be reheated. It'll be good for about 2 days then the grapes tend to break down.