Grease the inside of your slow cooker with cooking spray
In a large skillet, brown the sirloin
Drain the beef reserving about 1/4 cup of the grease
Put the beef and reserved grease back into the skillet
Add the garlic, chili, cumin, mustard, salt, sugar, black pepper, & cayenne
Stir the spices in and cook for a few more minutes
Transfer the beef mixture to the slow cooker
Add the tomato sauce, tomatoes, kidney beans, and pickled jalapeno peppers
Cover and Cook on high for 4-6 hours