Place slivered almonds in a dry skillet over low heat, and cook, & stir constantly, until almonds are lightly toasted, 3-5 minutes. Watch carefully, because, they burn easily. Remove almonds, and set aside.
Heat butter, in a skillet, over medium-low heat, and cook, and stir the shallots and red bell pepper, until softened, about 8 minutes. Sprinkle shallot mixture with sugar (if using), salt and pepper, and reduce heat to low. Cover, and cook slowly, stirring occasionally, until sugar dissolves and the shallots caramelize, 5-8 minutes.
Place a steamer insert, into a saucepan, fill with water, to just below the bottom of the steamer. Bring the water to a boil. Add green beans and cover. Steam, until just tender enough to pierce with a fork, 7-8 minutes. Drain beans, and place into skillet with shallot mixture; mix well, and gently stir in the toasted almonds. Makes 6 servings.