For pesto: Char peppers over gas flame or in broiler until blackened on all sides. Wrap in a paper bag and let stand 10 minutes. Peel and seed peppers. Grind roasted peppers, spinach, cheese, pine nuts, garlic and chipotle chilies in a food processor. With processor running, add oil; process until blended. Season with salt and pepper. For garlic sauce: Bring broth and whipping cream to a boil in a small saucepan. Add garlic and basil; simmer until sauce thickens slightly, about 20 minutes. Season with salt and pepper. ( Pesto and garlic sauce can be made 1 day ahead. Press plastic onto surface of presto; refrigerate. Cover sauce; refrigerate.) For chicken: Preheat oven to 400. Place 1 phyllo sheet on work surface so that 1 long side is parallel to edge of work surface (cover remaining phyllo with plastic wrap and damp towel.) Brush phyllo lightly with melted butter. Fold in half crosswise like a book. Brush with melted butter. Place 1 chicken breast so that 1 long side is 5 cm from bottom of phyllo, centering between sides of phyllo. Season chicken with salt and epper. Spoon 1 generous tablespoon of pesto over chicken. Sprinkle with quarter cup cheese. Fold bottom of phyllo over chicken. Fold short sides of phyllo over chicken. Roll up jelly roll style. Place seam side down on large baking sheet. Brush with melted butter. Repeat with remaining phyllo, chicken, pesto & cheese; refrigerate remaining pesto for another use. Bake until chicken is cooked through and phyllo is golden, about 25 minutes. Transfer to plates. Bring garlic sauce to a simmer. Spoon sauce onto each dinner plate, reserving some for a gravy boat type dish. Place chicken in center of garlic sauce. Garnish with fresh whole basil leaves.