That will make the base. Here is how you do it:
There are three critical tasks:
Make the roux. Heat the oil in a small saucepan under low to med heat, add flour slowly. Stir non stop for about 20 - 30 minutes. This is made less painful if you have a glass of wine to drink and some music playing. Don't try to rush it, or you'll end up having to start all over. When you get a pretty brown color and a nice nutty smell, it is ready. A suggestion, if you discover you like gumbo, make extra roux. It can be frozen for later use.
Slice the okra crosswise, and saute. It will do something very amusing. It is called roping - it will look like there are strings of cheese between pieces. When it stops making "new rope" (that is, a nice steady state) it is ready.
Adding the roux to the hot stock. Do a little at a time, try to have at the same temp, stir. You don't want the roux to separate. It always does a little on me, just stir.
Obviously 1 and 2 should not be attempted simultaneously. Unless you have someone to share the wine and cooking chores.
Stir in the fresh crushed chili. Now you have your base. Time to make it ready to eat.
The original idea was to use 7 or more greens. The exact interpretation and balance does not matter. Kale, collard, mustard greens, parsley, chard, escarole (my favorite), whatever you like. Saute an onion, green pepper if you like. Throw it all in, and 20 minutes later you have a nice gumbo. Sorry I don't give exact numbers. Still, a good guess might be 2.5 pounds greens to make this. A lot depends on personal preference. Gumbo should not be viewed as a special recipe, it should be a fun experiment. If you would like to make it more "meaty" than consider using some of the "fake meats" available in oriental grocery stores. Mock duck, mock abalone, mock shrimp, whatever, all work.
To serve: put a scoop of rice in a bowl, ladel gumbo over. Have some spoonbread on the side, or just ordinary cornbread.