Heat oven to 400 F. Grease 12-inch pizza pan. Unroll dough; place in greased pan. Starting at center, press out dough to edge of pan. Bake 10 to 12 minutes or until crust begins to brown.
Meanwhile, in 10-inch skillet, melt butter over medium heat. Cook onions and sugar in butter 20 to 25 minutes, stirring frequently, until deep golden brown and caramelized; stir in thyme leaves.
Spread cream cheese evenly over pizza crust. Top with Alfredo sauce, shredded chicken and caramelized onions. Bake an additional 10 to 12 minutes or until cheese is melted and crust is golden brown.