I can handle a lot of alcohol and I am full-fledged vegan as well. I need numerous drinks to get drunk.
Eat lots of starchy foods and high protein foods like Boca burgers or tofu. Or something high in fat like nut butters, hummus, and avocados. I wouldn't advise eating fruits, veggies, or high-fiber foods when drinking. I just noticed that when I eat "healthy" foods while drinking, I get sick. HUMMUS is excellent while drinking.
Also drink plenty of WATER. For every drink, you should have a 1/2 glass of water. I'm telling you. I never get a hangover if I drink water.