Green Beans and Pancetta with Browned Butter

2 lb. thin green beans or haricots verts, trimmed
4 oz. pancetta
2 shallots, thinly sliced
6 Tbsp. butter
6 oz. peeled and roasted chestnuts, sliced

1. In a 4-quart saucepan cook green beans, covered in boiling water 4-7 minutes or until crisp-tender. Drain and set aside.
2. In an extra-large skillet, cook pancetta over medium heat until crisp. Drain pancetta on paper towels, reserving the drippings in the skillet.
3. Reduce heat to medium-low. Add shallots to pan and cook for 4 minutes or until golden brown and beginning to crisp, stirring frequently. Using tongs, transfer shallots to a paper-lined plate. Season to taste with salt.
4. Add butter to drippings in skillet. Melt butter over medium heat. Reduce heat to medium-low. Continue to cook without stirring, for 4 minutes or until butter becomes light brown and fragrant. Reduce heat to low. Add chestnuts. green beans, and pancetta. Cook 2-4 minutes to heat through, stirring occasionally. Season to taste with salt and pepper. Serve immediately topped with shallots.