Heat the olive oil in a large pot over medium heat. Add the pork cubes and cook until browned on all sides, about 6 to 8 minutes. Remove the pork and set it aside.
Add the diced onion to the same pot and cook until it softens, about 4 minutes. Stir in the minced garlic and cook for 1 minute more.
Return the pork to the pot. Add the chili powder, cumin, cayenne pepper, salt, and black pepper. Stir to coat the meat and vegetables.
Pour in the diced tomatoes and chicken broth. Add the butternut squash cubes. Bring the mixture to a boil, then reduce the heat to low.
Cover the pot and simmer for 45 minutes, stirring occasionally, until the pork is tender and the squash is soft.