Peel and dice sweet potato. Boil/steam until soft. If using pre-cooked sweet potato, skip this step.
Mash sweet potato well (no lumps remaining). Allow to cool to room temperature.
Transfer sweet potato to a large mixing bowl. Add salt/pepper to taste.
Gradually begin to add 3 cups of flour, 1 cup at a time, mixing well with a wooden spoon.
As the dough becomes hard to stir, begin to knead in remaining flour. Add more flour if the dough is still sticky.
Flour counter top. Break dough up into 4 pieces. Take dough pieces one at a time and roll into a long rope (approximately 1.5" thick, or to desired thickness). Flatten the top slightly. With a sharp knife, cut the strips in individual pieces to form gnocchi.
Repeat with remaining dough.
Bring water to a boil. Add gnocchi to boiling water and let boil for approximately 8 minutes or until gnocchi rises to the top of the water.
Drain and serve with favorite sauce, or sautéed vegetables.
Freezes well uncooked (freeze individually, then put into a bag).

1 (approx. 750 gram) large sweet potato
4 cup all purpose flour, plus extra for rolling dough
Salt, to taste
Pepper, to taste