Place the slivered almonds in a dry skillet over low heat, and cook and stir constantly until the almonds are lightly toasted, 3 to 5 minutes. Watch carefully, because they burn easily. Remove the 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 the shallot mixture with sugar, salt, and pepper, and reduce heat to low. Cover, and cook slowly, stirring occasionally, until the sugar dissolves and the shallots caramelize, 5 to 8 minutes.
Place a steamer insert into a saucepan, fill with water to just below the bottom of the steamer, and bring the water to a boil. Add the green beans, cover, and steam until just tender enough to pierce with a fork, 7 to 8 minutes. Drain the green beans, place them into the skillet with the shallot mixture, mix well, and gently stir in the toasted almonds.