Don't Even Think About It!

I have a roommate named Dan. For those who have met Dan, you know that he is pretty even-tempered. It takes a great deal to get him to show much of any emotion. For the first few months I knew him while living at Rick's home, majority of our conversations were reduced to primal grunts.
Dan would come home and I would say "Hey. How are ya?"
He would respond. "Hey." or "Hm."
And I was ok with this. Depending on his tone or whether or not he used words, we could decipher what his response truly meant.
Since I moved to an apartment and Dan joined me a few months later, our conversations have increased. But, for the most part, Dan has remained rather quiet and keeps to himself. A "Hey, man." Or perhaps "Take care" when I leave the apartment is what has developed.
Things changed one night about a month ago.
Dan and I are both big Hamburger Helper enthusiasts. I have even branched out to the store brands in some cases. Monday nights were my night to create this culinary treat and on this particular occasion, I had selected the Cheesy Italian Shells dinner. I'm not one for cheese, but I trust the Hamburger Helper to never guide me down the incorrect path. While Dan passed the table, I casually mentioned "This may be better with some warmed up marinara."
It was then that Dan stopped in his tracks and pivoted to face me. "NO!" He cautioned. "Don't you ever, EVER adjust the Hamburger Helper recipe. The Hamburger Helper people have brought us their meals for generations and they know what they are doing."
I was taken aback slightly. "Ok. I won't-"
"Don't even think about it. The biggest mistake one can make is thinking that they can improve upon decades of intense research and countless study groups. These people know what they are doing and shouldn't be messed with!"
You would think that I was talking about over-throwing the government or something!
"I once made the same mistake that you are talking about. My meal was ruined. All effort was lost. You enjoy your Hamburger Helper the way that it was meant to be enjoyed - by using the directions that you find on the box."
It was that night that I made a binding vow to Dan, Hamburger Helper and the rest of the world to never again adjust or consider adjusting the recipe for Hamburger Helper.
Just don't tell him that I will on occasion add a bit more milk and spice up the meat. I am concerned with what he may do if he knew.