Clean the beef and set season with onion powder, bouillon season (if you’re using) salt and pepper. Set aside.
Bring about 2 quarter of water in a medium-size pot, season with salt and add the pasta. Cook according to the package instruction but 1 minute less the cooking time.
Drain drizzle oil over the pasta (to avoid sticking together) and set aside about ½ cup of pasta water.
While the pasta is cooking, place a wok or pan over high heat add heat the oil, add the seasoned beef (single layer) and cook on both sides, about 3 minutes more depending on the beef size. Remove and set aside.
In the same pan, sauté garlic, onion for a few minutes, don’t burn the garlic, add the sweet pepper (you can also use bell peppers) and stir. Cook for about 1 minute.
Add the tomato sauce and combine, add the broth, parsley. Season with bouillon powder/cube (if you're using), salt and pepper, cook until the tomato sour taste vanishes.
Add the red pepper flake, return the beef with all the juice and stir. Cook for about 1 minute and allow the beef absorbs the sauce.
Add the cooked pasta, about ½ cup of pasta water and stir. Allow the pasta to cook all through and absorb the sauce. Add the chopped spinach allow the spinach to wilt.
Check the seasoning and readjust if necessary then take off the heat.
Serve and enjoy!