In a large skillet, heat oil over medium heat and add beef, onions, salt and pepper to taste, cinnamon, and nuts; cook until beef is no longer pink. Remove from heat and let cool.
In a large mixing bowl, combine flour, salt, eggs, and water; mix until dough is smooth. Roll the dough into a ball and cut into 10 pieces.
On a floured board, roll flat each piece of dough; cut out 5 circles, about 3 inches in diameter. Place about 1 teaspoon of meat filling in the middle of each circle; fold the dough over and seal the edges with a small amount of water.
Bring a large pot of lightly salted water to a boil; drop in kreplach a few at a time. Cook for 4 minutes or until kreplach float to the top. Remove with a slotted spoon; serve.
