Pre-heat oven to 350 degrees. Grease and flour bread pan and muffin cups (or use muffin cup liners). Begin by mixing the sugar and shortening thoroughly. Then add eggs, then mashed bananas. Next, I add in the small ingredients; salt, vanilla, etc. To make the sour milk, I put a teaspoon of lemon juice in a 1/2 cup and then fill it the rest of the way with milk. You can use 2% or skim milk, it's entirely up to you. Then it's time to add the flour. This will thicken what is now a very moist mixture. Add nuts if desired. I measure muffins with an ice cream scoop or a tablespoon and just eyeball that they are even. Muffins are baked for 10-15 minutes, or until an inserted toothpick can come out clean. Bread loaves would be baked for 45 to 50 minutes.