Pile asparagus onto a baking sheet and drizzle with some extra-virgin olive oil and season with some salt and pepper. Transfer to the grill and cook turning every now and then until the asparagus is well marked and is tender, about 5 minutes, depending on the size of your asparagus.
While the asparagus is grilling in a bowl combine the tangerine zest and juice with a little salt, pepper and a small dash of hot sauce. Add the heavy cream and whisk to aerate the cream. Remove the asparagus from the grill, top with sliced onion and basil and serve hot, warm, or at room temperature with the sauce poured over it.