In a saucepan, heat the olive oil over medium heat. Add the onions and saute for 5 minutes until golden and tender but not browned. Add the garlic and saute for 1 minute.
Carefully pour in the vegetable broth, and then add the remaining ingredients: tomato paste, adobo sauce, cumin, oregano, garlic powder, chili powder, and kosher salt. Bring to a simmer, where the sauce is gently bubbling, and simmer for 15 minutes.
Carefully transfer the contents to a blender (use a ladle to keep from splashing). Blend until smooth. Use immediately or place in a jar and refrigerate for up to 2 weeks.