Pasta e Piselli

Ingredients:
1 Small Onion, finely chopped
4 Slices of Bacon, chopped
2 ¼ cups of Frozen, Defrosted Peas
12 oz of small cut pasta such as small shells or tubbettini
1 Tbsp of Olive Oil
1 Tbsp of Unsalted Butter
Freshly Grated Parmiggiano to taste
4 cups of Water
Salt and Pepper, to taste