Place tortilla on parchment paper on a baking sheet and spray it with cooking spray (like canola). Bake for 10 minutes. Remove from oven and set aside.
Meanwhile, combine ricotta, lemon juice, lemon zest and sweetener in a small bowl and set aside.
Add grape juice and balsamic vinegar to another small bowl, cover and microwave for 2 ½ minutes until thickened to a syrup consistency that will coat a spoon. It will thicken more as it cools. You will have approximately 1 teaspoon of drizzle when finished.
Spread ricotta mixture on the tortilla.
Top with fruit arranging the strawberries on the outer edge, then blueberries in a circle at the end of the strawberries. Place raspberries and blackberries in the center.
Drizzle with the grape syrup and sprinkle with extra lemon zest for garnish. I add the syrup to a small plastic sandwich bag and cut the corner to drizzle it on for better control.
Slice into 6 slices with a pizza cutter and serve.
Notes
Enjoy the whole tart for a fiber and protein rich breakfast or 1/2 for a heart-healthy dessert.