This recipe has been made in my family for years, I've even started passing it on to friends as they enjoy it a lot! For a treat, add a dollop of sour cream to finish if you're not vegan (although vegan sour creams are available in some health stores).
Heat oil in a large saucepan. Add onions and garlic and cook until light golden.
Mix in 3 teaspoons of the Mexican seasoning, then add tomatoes, Vegemite, Worcestershire sauce, stock, lentils, tomato paste and sugar. Bring to the boil and stir, then reduce heat and simmer for 45 minutes.