A Southwest twist on an old classic!
Cut beef into 1/2 inch cubes (bite-size). In a medium bowl mix together the 5 spices and salt. Add the diced beef and toss well to coat. (This step can be done up to 24 hours in advance).
Add the beef broth and minced chile and bring to a simmer. Cover and braise on low for one hour (*note* if you opted not to cut your meat as small as 1/2 inch pieces, then your cook time will have to increase). Check for tenderness. Meanwhile, peel and ribbon your sweet potatoes.
After one hour, the meat should be tender. If not, continue simmering and check every 20 minutes. Ladle 1/4 cup of the beef broth into a measuring cup and whisk in the cornstarch. Slowly add the cornstarch mixture back to the meat and stir well. Cook for a few minutes until you see the sauce thicken. If the sauce is not thickened to your liking, ladle out more broth and add another Tablespoon of cornstarch, then reincorporate it into the sauce.
Add the sour cream and warm through. Stir to combine and sprinkle with cilantro. Serve over sweet potato ribbons.
Use a vegetable peeler to make long thin ribbons of sweet potato. (If you are using store bought sweet potato noodles, just follow the directions below for roasting).
Roast for 10 minutes. Check for a soft but not soggy texture. You want them to have a little bit of chew to them still.