In a medium saucepan over medium heat, combine apple cider vinegar, ketchup, Worcestershire sauce, brown sugar, molasses, hot sauce, garlic powder, yellow mustard, smoked paprika, black pepper, salt, and crushed red pepper flakes (if using). Mix all the ingredients together until well combined.
Allow the sauce to simmer gently for about 15-20 minutes, stirring occasionally, until it thickens slightly and the flavors meld together.
If the sauce is too thick, you can add a little water to reach your desired consistency.
Taste the sauce and adjust the seasoning if needed. You can add more salt, pepper, or hot sauce according to your preference.
Notes
Feel free to adjust the ingredients according to your taste preferences.