...or food intolerance?
I have food allergies, and while onions and peppers aren't typically found in cake, I know what happens if I accidentally ingest them. The experience can be miserable for some and life threatening for others.
I bake all of my cakes in my kitchen at home, which you are welcome to visit. You will see that I am fastidious about cleaning and sterilizing my equipment and about cross contamination issues.
In the interest of your safety and satisfaction, if my website was a food label, it would say, "The cake you are about to eat was manufactured in a facility that also processes items with milk, tree nuts and peanuts, dairy products, soy products, and gluten."
Again, as a food allergy sufferer, I take these issues very seriously. Please be certain to tell me the items you are concerned about and raise your concerns with me.