In a sautรฉ pan over medium high heat, cook sausage, stirring and breaking up with a spoon. Cook until sausage is fully browned, about 10 minutes. Remove from heat and set aside.
Heat oil in another sautรฉ pan over medium heat. Add onion, thyme, and salt. Lower heat to medium low and cook until onions become soft and caramelized, about 15 minutes. Set aside.
Place cream cheese in a large bowl and mix until smooth. Add mozzarella, caramelized onion, lime juice, diced tomatoes, and about โ of the scallions. Mix well, then gently fold in chorizo.
Spoon mixture into greased baking dish. Place dish on a baking sheet and bake for 18-20 minutes, or until dip is golden and bubbly.