Heat oven to 375°F. Place pizza crust on ungreased cookie sheet. Spread with mustard.
In 10-inch skillet, melt butter over medium-high heat. Cook onions in butter, stirring occasionally, until tender.
Spoon onions evenly onto pizza crust. Sprinkle with cheese and almonds. Bake 15 to 20 minutes or until cheese is melted. Cut into wedges.