"Vintage" Chocolate Pudding...Clear...crisp...cool...40's

Here's one of my Mom's recipes, at least 50 years old. You can see how much it's been used. 
Isn't her handwriting lovely? She and her sisters had such pretty flowing script,
 back in the day when handwriting was still emphasized in school!

6 T. cornstarch
1/2 cup cocoa
few grains of salt
1 cup sugar
1 quart milk
1 tsp. vanilla

Here's the procedure ------------
Mix sugar ( I reduce to 2/3 cup) cornstarch and cocoa in a heavy
bottom pan.  Add milk while stirring over medium heat.
Continue to stir until thickened and just starts to bubble.
If you have to answer the phone,  the door, or check Facebook remove from heat, it will catch on bottom and burn!
Add vanilla, pour into bowl, cover with plastic and let cool or chill in refrigerator.
Says feeds 6, but not at my house!