Grilled Mahi Mahi with Ginger and Wine

8 oz. Mahi Mahi fillets
6 shallots, coarsely chopped
4 quarter-size slices fresh unpeeled ginger
1 clove garlic
3 tbsp unsalted butter
1/2 cup chicken broth
4 tsp cornstarch
1/3 cup dry white wine
1 tbsp fresh lemon juice
2 tsp grated lemon zest
1/2 tsp freshly ground black pepper

Preheat grill or broiler; spray a grilling basket or broiler pan with nonstick cooking spray and arrange the Mahi Mahi fillets on top. In a food processor, mince shallots, ginger and garlic.
In a small skillet, melt butter. Add shallot-ginger mixture and cook, stirring until just golden, 8 - 10 minutes. Remove skillet from heat.
Brush Mahi Mahi fillets with half the ginger-shallot mixture. Grill or broil 4 - 5 inches from heat, turning once, until lightly colored and the flesh just flakes when tested with a fork, about 6 minutes.
In a small bowl, blend together chicken broth and cornstarch. Return skillet to medium heat and stir in wine, lemon juice, zest, and pepper. Bring to a boil, add cornstarch mixture and return to a boil, stirring constantly.
Reduce heat to medium-low and simmer, stirring occasionally, for 1 minute or until thickened and slightly glossy. Transfer fillets to plates and drizzle shallot-ginger glaze over them