Add the oil to a dutch oven and heat over medium heat. Add in the ground beef and brown, breaking up as it cooks. Once completely browned, strain the meat and then return it to the pot.
Stir in the onions and garlic, cooking another 3-4 minutes- just until the onions are tender and becoming translucent.
Stir in the flour, and continue to stir constantly while cooking, for one minute- to cook out the 'floury' taste.
Add in the spices, sauce, and broth- stirring to deglaze the pot. Stir in the pasta and put the lid on the pot. After a couple minutes, check that the mixture has come to a simmer.
Reduce the heat to low, stir the pasta and replace the lid. Allow the mixture to simmer, stirring occasionally to prevent sticking, for 15 minutes- or until the noodles have absorbed the liquid.
Remove the dutch oven from heat and stir in the cheese. Serve the chili mac topped with extra shredded cheddar, if desired.