Your best bet for ripe tomatoes is to buy them from a local farmers market or farm stands as they’ll have what’s in season. If you’re buying from the grocery store, look for tomatoes that have a vibrant red hue and are firm but give slightly to gentle pressure. You’ll also want them to have a sweet earthy aroma near the stem. If your Roma tomatoes are not in season or they are not the best quality, you may need to adjust the flavor by adding a little sugar or honey to help replace any lost sweetness and flavor. Or, use sweet cherry or grape tomatoes instead.