(Don't get too over-eager in adding spices to the mayonnaise. You don't need any. Only exception might be a bit of red pepper flakes or an herb of your choosing such as oregano or basil - go easy!)
Since fat is flavor and mayonnaise is mostly made up of oil and egg yolks (both of which are fats), mayo translates to more flavor. So next time you toss a steak on the grill, use a brush to baste the meat with a little bit of your favorite mayonnaise, just like you would with melted butter or an infused oil. Not only will this add richness, but it will also help to keep the meat juicy while it cooks. Another upside to using mayo: It’s better than your non-stick pans. Think of it as non-stick insurance when grilling delicate proteins such as fish or flimsy vegetables like zucchini and eggplant. We’ve all experienced these foods sticking to grill grates and ultimately ruining our backyard barbecue, having to serve mangled remnants of our intended menu. Avoid this by simply adding a very thin layer of mayonnaise to anything you think will cling to the grill, before cooking, to assure that your dinner will release with ease.