Preheat oven to 400°.
If using fresh peas, remove pea from pods; discard pods. Cook peas in boiling water 1 minute. Remove peas with a slotted spoon and place into ice water; drain.
Arrange prosciutto in a single layer on a baking sheet coated with cooking spray; bake at 400°F for 7 minutes or until crisp. Set aside.
Bring broth and water to a simmer in a medium saucepan. Keep warm over low heat.
Melt butter in a pan over medium-high heat. Add leeks and garlic, saute 3 minutes or until tender. Add rice and thyme and cook 2 minutes, stirring constantly. Reduce heat to medium. Add white wine and cook 1 minute or until liquid is almost absorbed, stirring constantly. Add broth mixture, 1/2 cup at a time, stirring frequently until each portion of broth is absorbed before adding the next Stir in peas, salt, and pepper.
Remove from heat. Stir in arugula and Fresh Mozzarella cheese. Top with prosciutto.