Heat an oven-proof stockpot or Dutch oven, on medium. Add the ground beef, as well as: 2 Tbs chili powder, 1 Tbs cumin, 2 tsp kosher salt, 1 tsp ground black pepper, 1/8 tsp cayenne pepper, ½ tsp cinnamon, ¼ tsp coriander, ¼ tsp cardamom, and ¼ tsp. Stir to incorporate.
While the beef is browning, you can chop the red pepper. When the beef is mostly browned but still has some pink color, add the red pepper to the pot and sauté for 3 minutes or so.
Meanwhile chop the onion and add it to the pot, sauté for another 3 minutes or so.
As the onion is sautéing, you can mince the garlic, and then add it to the pot. Stir the garlic frequently being careful not to burn it. Burned garlic is bitter, and can ruin a dish. My Aunt Rose taught me that when you start to smell the garlic, it is time to get it off the heat or add something to the pan that will bring the temp down.
At this point, if you have a lot of grease in the pan you can drain it off (not down the sink!), otherwise you can add the tomatoes, the beef broth, and the unsweetened cocoa.
Bring to just a boil, cover and then put the pot into a 350-degree oven for at least an hour and a half. This should bring the flavors together, reduce some of the liquid, and tenderize the beef.
Stir in 3 cups of diced butternut squash, during the last 20 minutes of the chili's oven time. When the squash can be easily pierced with a fork, it is ready to eat. If it is still too firm, bake for another five minutes and then check again.