Heat the oil in a medium pot and fry the garlic over medium heat until golden. Add the smooth tomatoes, sugar, salt and pepper and bring to a boil. Simmer uncovered for about 15 minutes or until reduced by a third. Set aside.
In a wide pan, heat the oil and fry the onions, fennel and lemon rind until it is soft and fragrant. Remove from the heat and transfer to a mixing bowl, adding the smoked paprika, mince, salt and pepper. Mix well.
Shape into balls (about 4-5cm in diameter).
Using the same pan as before, add more olive oil and fry the meatballs on all sides over medium heat until just cooked. Serve with the warm tomato sauce, scattered with fennel fronds (and pasta/starch of your choice, optionally).