Peel your potatoes, and dice them into about 1 inch size bits
Place in a microwave safe container and microwave for about 5 minutes.
Mash your sweet potatoes with a fork or potato masher.
Melt butter in a medium frying pan
Saute onions in the butter for about 5 minutes
Add onions to mashed sweet potatoes and stir together.
Add egg, flour, and salt to sweet potatoes and mix together.
Preheat a frying pan to medium heat and add butter to the pan. Scoop up about 1/4 cup of the mashed mixture and place into a frying pan, heated to medium.
Scoop up about 1/4 cup of the mashed mixture and place into the pan.
Pat down to about 1/2 inch thickness, and 2 to 3 inches in diameter. (The patties may be a bit sticky and hard to shape, coat hands in nonstick spray as needed.
Fry for about 60 seconds on each side.