There is a famous old cartoon: your basic middle-class family seated around the dinner table, the boy snarling at his parents, "I say it's spinach and I say to hell with it!"

We can't be sure what was said to set off this outburst. But I can imagine the well-bred mother saying, "Eat your epinards , dear." Or maybe the boy asked what he was eating and the father said, "That? Oh, that's chicken Florentine." Or eggs Florentine. Or almost-anything-at-all Florentine.

Whenever someone slips the word "Florentine" into a cooking conversation, it's just a slightly pompous way of saying "with spinach." It would have been as accurate to call this "chicken with spinach" - but a dish this good deserves just a touch of pomposity.

Incidentally, if the kid in the cartoon grew up to enjoy cooking, you can be sure he changed his attitude. It doesn't take long for a cook to develop Popeye's respect for spinach - not just for the way it can stand on its own but for its social nature, the way it mixes into almost any surrounding.

The Staples: Make sure these are all on hand: salt, pepper, marjoram, butter, lemon, sherry, rice, flour, sugar.

The Shopping List: 2 pounds of boneless chicken breasts; 1 pound fresh spinach; 1 bunch fresh rhubarb; 1 bunch scallions; 1 can chicken bouillon; 1 frozen pie crust; 1 small can Turkish or Greek coffee.

5 P.M.: The last shall come first. Although the rhubarb pie can be made earlier in the day, there's no need to go to all that trouble.

Pre-heat oven to 450 degrees. Rinse off the rhubarb stalks and chop them into small chunks. You'll need about 4 cups of the fruit. Mix the rhubarb pieces with 1 1/2 cups of sugar, the juice of half a lemon and a small fistful of white flour.

For years we've heard discussions about the difficulty of achieving the perfect pie crust. And that is why today we're going to use a frozen pie crust, following the direction on the package.

5:15 P.M.: Spoon your fruit mixture into one of the pie shells. Use the second pie shell as the top crust. Seal top crust to bottom crust with a little water. Trim off any excess dough. Put the pie in the oven.

5:25 P.M.: Lower oven temperature to 350 degrees. The pie should be baked in 40 minutes.

5:30 P.M.: The most difficult part of the meal will be the chicken, so we'll turn to that next. Rinse the chicken breasts under cool water and pat them dry with paper towels.

Put a cup of flour in a mixing bowl, add a dash of salt and pepper, then dust each chicken breast in the flour. Melt 1/2 stick of butter in a large frying pan over medium heat and then add the chicken breasts. Sprinkle marjoram generously over each breast and cook for 6 to 7 minutes on each side. (Danger! An overcooked chicken breast is a tough chicken breast.)

Add a splash of sherry and swirl it around the frying pan. When most of the wine has cooked away, put the chicken breasts in an oven-proof dish.

6 P.M.: Make rice according to box directions, substituting 1 can of bouillon for an equal amount of water and adding a handful of chopped scallions at the same time as you put in the rice.

6:05 P.M.: Remove pie from oven and replace it with the chicken. Turn the oven down to 250. Okay, the chicken is hot in the oven and the rice is cooking over a very low heat. What now? Now the spinach. One thing you should know about fresh spinach: it's sandy. Even when the package says it has been rinsed, it is sometimes sandy. Rinse each leaf in a container of cool water. And once again.

Chop the spinach and put it in the frying pan you used for the chicken breasts. Over a medium heat cook the spinach in the wine and butter and chicken scrapings left there from your earlier efforts. If the frying pan seems to be drying out, feel free to add another chunk of butter, another splash of wine, or both. In fact, do this even if the pan isn't drying out. The spinach will cook in about 5 minutes.

6:20 P.M.: Mix the spinach and the pan residues in with the chicken and keep it hot in the oven. It is difficult to tell whether the juices from the chicken lend flavor to the spinach or whether it's the other way around - either way, it's one of those rare marriages that improves both participants.

6:30 PM: Check the rice. Add butter. Remove chicken from oven and squeeze a lemon half over the dish.

After dinner, just before serving the rhubarb pie, sneak back into the kitchen and make some Turkish coffee. Although it is simple to make, it is rare enough to offer a perfect finishing touch to the meal.

To 2 cups of water add 8 teaspoons of the finely pulverized coffee and an equal amount of sugar. Let the coffee come to a boil and pour the froth that forms into demitasse cups. Then put the coffee back on for another quick boil. Fill the small cups with the second supply of froth and serve. (Danger! Do not stir the coffee once it has been poured because what you will have then is nnot coffee; its name will be mud.)