The salsa is simple just things from the garden tomatoes, peppers (salsa and a little ancho) garlic, onions and cilantro.
If I have them I use roasted peppers
As for freezing I make it simple just onions peppers and tomatoes in my blender till smooth , pour into a freezer bag and freeze. Just too busy or lazy to things that take time, and I hate to waist fresh garden produce .
It is the base for chilly or pasta sauce , also great in veggi soup.
