Combine all the marinade ingredients in a bowl and mix well to combine. You may need to use the back of a spoon to break up the tamarind pulp. You can also use a blender if you'd like the marinade to be more uniform.
Add beef, mix and refrigerate for 24 hours or overnight.
Remove the beef from the fridge and put on bamboo skewers. **to prevent the bamboo skewers from burning, soak them in water for 20 minutes before skewering the beef.
Heat grill to 400F. Cook beef skewers about 10-15 minutes, flipping every couple of minutes to ensure even cooking.
Let rest for 5 minutes. Serve with basmati rice and peanut dipping sauce.
Peanut Dipping Sauce
Combine all the ingredients in a blender and pulse until smooth. Add additional water if the sauce is too thick.
It is more traditional to cut the beef in strips, but I find it easier to use pieces. Feel free to cut it in 1" strips instead of pieces if desired.
Soak the bamboo skewers in water for 20 minutes before using the. This helps to prevent the ends from burning. You can also use metal skewers.
Substitute the beef with pork, chicken, tofu or shrimp if desired. Try these Thai Shrimp Skewers.
You can serve with basmati rice, jasmine rice, brown rice, or any other rice you prefer.
Add additional chilies to the peanut sauce for added spice.
If the peanut sauce is too thick, add additional water, a little at a time, until the desired consistency is reached.