There is a theory when it comes to treating allergies that if you give the patient tiny little bits of the item they are allergic to over a period of time, they will eventually be able to tolerate those allergens. This works mostly with treatable allergens such as dust and mold. The sad thing about food allergies is that no serum has yet been created (they’re close with peanuts). Your only option is one the allergist glibly refers to as “avoidance”.
I’m pretty good about avoidance, for the most part. I eat the plasticy soy cheese, drink soy milk, soy sour cream, etc. I can be satisfied with soy alternatives for some foods, and I’m more than happy to not be supporting the mainstream dairy industry. But there is no soy-based replacement for really beautiful artisanal cheese.
Thus, there are times when you just have to look Death in the face and say, “Fuck you, Death! I am eating this brie!”, and be willing to live (or not) with the consequences.