Everyone should have a casual restaurant in their life — a place where you feel comfortable. You go in, you slide into your seat and you order exactly what you always order — no menu necessary. These sorts of places are usually the greasy spoon spots of the world. The 24-hour, one-in-every-town places where you always know exactly what you’re going to get.

At least until they screw things up by tampering with the menu.

And this leads me to the shock of my comfort dining life.

On Saturday night I eased into a booth at Denny’s and didn’t even bother to crack open the menu. I KNEW what I was going to get. I had been craving it for hours. It was the same thing I always get at Denny’s: A patty melt with fries.

But when I gave my order to the waitress, she gave me a puzzled look. She said something like “What? We don’t have that,” and all hell broke loose.

“You don’t have patty melts anymore?” I stammered unbelievingly? “That’s the only reason I came here!”

To add insult to injury, her next act bordered on unforgivable. In an attempt to assist me in my shock, she pointed me toward a possible substitute: A Philly cheese sandwich. With ROAST BEEF!

OK, yes, roast beef does come from the same animal as beef, but come on! A Philly cheese sandwich does not a patty melt make. Not even close.

In a last-ditch effort to salvage my meal, I asked if they had rye bread. Nope. No rye bread.

This is a travesty of American family chain restaurant justice. No rye bread! So when Mr. Jones in Omaha, Neb., goes to order his morning eggs, the toast offerings are what — white, wheat or focaccia?

Being as it was — 10:30 p.m. and out of restaurant options — I settled for a mushroom swiss burger.

I was sorely disappointed. The untoasted soft sesame bun seemed like a weakling 90-pounder on the beach compared to the crisply toasted slices of buttered rye bread that cradle a well-made patty melt.

The mushrooms were lackluster and the burger slightly dry. It was cluttered with needless romaine, pickles and red onion.

I noticed that grilled onions, the piece de resistance of any patty melt, didn’t appear on any of the new fangled burgers on Denny’s modernized menu. Red onions were on everything.

Now I have nothing against red onions. They are perfectly lovely on a sandwich or in a salad. But a heap of grilled yellow or white onions are a staple of the American diner scene.

I left with a bittersweet feeling. Denny’s was the go-to place of my midwestern childhood. In high school it was the only place we felt comfortable — or could afford. In college it was open late enough for post-bar cravings, and many a greasy meal was devoured into the wee hours.

In recent years, it was a place we looked forward to eating at with the kids during long road trips — when we needed somewhere where we could be sure of what we’d get.

RIP: Denny’s patty melt. I’ll never stop for the yellow sign again.

– Kari Hulac