Several hours before starting, place pizza dough on the counter on a floured surface. Sprinkle a little flour on top. Cover with a clean tea towel. Preheat oven to 400ºF. Line a baking tray with parchment paper. Place cut sausage, onions, and peppers on the tray in a single layer. Drizzle with couple of tablespoons of olive oil. Sprinkle oregano, fennel, salt and pepper over everything. Place tray in oven and roast for about 25 minutes, or until onions and peppers are soft. Remove tray from oven and set aside. While sausage and peppers are in the oven, make the tofu ricotta cheese. Wrap tofu in paper towels and press gently on counter, on all sides, to remove excess water. Crumble tofu into a medium bowl. Add remaining ingredients and stir to combine well. Set aside. Punch down dough and divide into 8 pieces. Line a baking tray with parchment. On a lightly floured surface, roll each piece one at a time, into a thin circle. Spread with a couple of tablespoons of ricotta on one half of the circle, leaving about a 1/4 inch border to create a seal. Take a heaping spoonful of sausage and pepper filling and place it on top of ricotta. Fold over one side of dough to cover the filling to create a half moon. Use a fork to press and pinch the edges together to create a seal. Lift calzone with a floured spatula and place on prepared baking tray. Repeat until ingredients are used up. With a sharp knife, cut a small slit in each calzone to allow steam from cooking to escape. Brush calzones with olive oil and sprinkle with little salt. Place tray in oven and bake for about 15 to 20 minutes, or until dough is nicely browned all over. Use a spatula to lift calzones and check the bottoms at the 10 minute mark. Let sit for a few minutes before serving. If using tomato sauce for dipping, heat it up while calzones are baking.