The secret to this recipe is that the tomato and sausage is roasted on a sheet pan rather than the stove top. Maybe this means it doesn’t technically qualify as sauce, but it taste delicious, and it requires much less attention than trying to brown onions in a skillet.
Because this recipe has just a few ingredients, look for quality. While roasting cherry tomatoes will concentrate their flavor, improving even mediocre ones, if you know local farm or neighbor with a big garden, it is worth an extra trip. Add good olive oil and great sausage and you can’t go wrong.