Preheat oven to 400 degrees F (205 degrees C) and line two quarter sheet pans with parchment paper.
Arrange grapes onto one of the parchment-lined sheet pans, drizzle grapes with olive oil and season with a pinch of salt.
Arrange the thinly sliced Fennel Bulb (1) on the other parchment-lined sheet pan and drizzle with olive oil and season with a pinch of salt.
Roast Grapes (1 pound) and fennel in the oven.
While the grapes and fennel roast start the white balsamic reduction. Add White Wine Vinegar (1/2 cup), Agave Syrup (1/4 cup), and Fennel Seeds (1 teaspoon) to a small saucepan and whisk to combine
Cook over medium heat until the liquid comes to a simmer. Simmer for 10-15 minutes until reduced to about 1/3 cup. The mixture should be thickened and coat a spoon when adequately reduced. Pour the reduction into a small dish and reserve.
Remove the grapes after 20-25 minutes. They should have started to release their juices and the skin will look wrinkly.
Continue roasting the fennel for another 10 minutes, until it has softened and looks slightly caramelized.
While the grapes and fennel cool, mix the Vegan Ricotta Cheese (8 ounce) and Vegan Cream Cheese (8 ounce) cheese together in a bowl until the mixture is well combined and smooth.
Arrange the torn Radicchio (1 head) onto a large platter. Drizzle the radicchio with Extra-Virgin Olive Oil (to taste). Add caramelized fennel over the top of the radicchio.
Next, add dollops of the vegan burrata ricotta (you should have about 1/2 of the bowl leftover). Add the roasted grapes and Castelvetrano Olives (1/2 cup).
Drizzle the finished salad with the fennel white balsamic reduction and garnish with Coarse Salt (to taste).