Sure you can buy roasted peppers in a jar at the supermarket, but there is really no reason to do that when it is so easy to roast your own. After I roast the peppers I like to store them in an airtight container tossed with some extra-virgin olive oil and sliced garlic. They will last about 2 weeks in the fridge.
Roasted peppers have so many uses I won’t try to list them all here. But, just to name a few, they can add a little punch to crostini, mozzarella salad, cold antipasti, and sandwiches. You can even use them in a Hand Rolled Lasagna .