Please choose the correct solution to the question: Potato Cakes

Solution1: Add butter, flour and an egg to mashed potatoes and mix until it becomes a dough. Kneed out the dough and cut circles from the dough. Put them into a pan with oil and fry, flipping so each side can be browned.

Solution2: Add butter, water and an egg to mashed potatoes and mix until it becomes a dough. Kneed out the dough and cut circles from the dough. Put them into a pan with oil and fry, flipping so each side can be browned.

Answer format: solution1/solution2
Answer: solution1