Vegetable Burger at Mos Burger

Finally saw vegetable burger at Mos Burger! I haven't eat Mos burger for more than a year after I start on vegetarian diet. But I'm not sure if the sauce is vegetarian.I hope it is. If the restaurant is willing to spend time to come up with vegetable patty, they should also some time on ensuring the sauce doesn't include meat too. 

Saw a vegetable symbol so brought to try. This Hokkaido croquette is delicious and taste like filet o fish. Really crispy on the outside and smooth inside with similar texture to Macdonald filet o fish patty. Love the croquette. If the sauce is not vegetarian, I just order the croquette which is yummy.