Related: Spinach Pesto Recipe
1. Toast hazelnuts in skillet 3 to 5 minutes, or until golden, shaking skillet often. Cool, coarsely chop, and set aside.
2. Meanwhile, bring large pot of water to a boil. Cook broccoli in boiling water 2 to 3 minutes, or until tender. Remove with slotted spoon. Drain, and rinse under cold water. Drain again.
3. Pulse hazelnuts, broccoli, parsley, oil, mint, lemon juice, lemon zest, capers (if using), and garlic in food processor until smooth. Season with salt and pepper, if desired.
4. Cook farfalle according to package directions in broccoli cooking water. Reserve 1/4 cup cooking water before draining. Toss farfalle with pesto and pasta cooking water. Garnish with toasted hazelnuts, if using, and drizzle with olive oil, if desired.