Finely chop the onion and garlic.
Add olive oil to a pan and sauté the onion and garlic over low heat.
Add tomato paste and cook for 3 more minutes.
Add erythritol, gochugaru (Korean chili powder), soup soy sauce, and vinegar, and mix well.
Simmer over medium-low heat for 5 minutes, stirring occasionally.
Let the finished low-sugar gochujang cool before storing.