Cut each zucchini in half lengthwise. Use a small spoon and scoop and scrape out enough zucchini flesh to create a zucchini shell to place the stuffing in. You should have about a 1/2” wall of zucchini remaining on each shell. Place these zucchini shells on a large baking sheet.
Coarsely chop the flesh you scraped out of each zucchini. Heat the oil in a wide skillet set over medium, medium-high heat. Add the onion, chopped zucchini, garlic and tomatoes and cook and stir until all are softened, about 5 minutes. Remove from the heat, and then mix in the oregano, chili flakes, breadcrumbs, salt and pepper.
Divide and spoon this mixture among the zucchini shells. (Each won’t be overly full, because you’ll need room to set the toppings on.)
Preheat your oven to 375°F. Divide and top each zucchini shell with quartered artichoke hearts, olive halves and nuggets of goat cheese. Now top with the grated asiago cheese.
Bake the zucchini, uncovered, for 25 minutes, or until the shells are tender and the filling and toppings hot and light golden. Top each stuffed with some sliced basil and serve.