Mix all of the ingredients together until they are well-combined. Adjust the amount of horseradish slowly, adding more until it tastes as spicy as you like! This is a very personal thing so this will vary for each of you!
Add in more sugar if desired. The sugar cuts the acidity of the ketchup and lemon juice just enough to balance out the flavors.
Store in a closed container in the refrigerator until you are ready to use.
Notes
Nutrition is for one ounce of sauce. Everything will vary depending on the brands that you use in this recipe.See my tips in the post above for making this sauce lower in carbs.