There is a very small restaurant in Los Angeles on Sunset Blvd. (Silverlake area of L.A) called, Heywood Gourmet Grilled Cheese Shoppe. They specialize in grilled cheese sandwiches.
However, they are EXPENSIVE! Average price is $12.00 for a grilled cheese sandwich. Does come with a small side salad and small cup of soup but is a little too expensive for me. I went in there once maybe a year ago. I had gotten off my bus one stop too soon (didn't know the area all that well) and noticed this restaurant. I was hungry & also had to use the restroom so I thought - well, I'll just pop in here and get a grilled cheese sandwich. I was thinking (before I saw the menu) that it might be around $7.00 or $8.00 (as it is kind of become a trendy hipster area in recent years.
I was shocked to see $12.00 for lunch (did not include a beverage)
OK, so since I was there and hungry I ordered the grilled cheese sandwich and ran to the restroom before my order was ready. :-)
Most restaurants frown on people just coming in to use the restroom without dining there in Los Angeles.
I have to admit the sandwich was really good! Wonderful cheese they use - but just too expensive for me to go back again.   
I think they are online & show their menu. Too bad they are so expensive though. That is not typical though for the price of a grilled cheese sandwich. You can find it for 1/2 that price or less at a regular coffee shop restaurant (in a less trendy area.)
But since this is a specialty place for grilled cheese their prices are much higher I guess.