The case
The Thanksgiving shortcut in the red box has been in the pantry since 1972. Ask who makes it and a lot of people will say Stouffer's, and some remember the name on the box.
Stouffer's is the frozen-lasagna company. Two food brands that start with "Sto," both sold as easy dinners, get filed together, and the more famous name takes over the box.
Why our brains do this
Similar-sounding brands in the same aisle merge, and the better-known one absorbs the other's products.
Sources: Wikipedia — Stove Top stuffing · Wikipedia — Stouffer's · Wikipedia — False memory: the Mandela effect