Grate the zucchini, finely dice the onion and garlic. Also dice the smoked bacon.
Leave the bacon in a little olive oil. Add the onions and sauté. Then add the zucchini and garlic to the pan and stir-fry. Season to taste with salt and pepper.
Drain the spaghetti and mix with the zucchini. Parmesan on top - done!
The zucchini will not be a real sauce but rather have a consistency like pesto.