If using fresh spinach, blanch it in boiling salted water for 1-3 minutes.
Rinse the spinach under cold water, squeeze dry in a dish towel and chop.
Heat oil in a nonstick skillet, add the scallions, garlic and ginger cook for 3 minutes until the scallions begin to soften.
Add the diced tofu and sesame seeds and cook for 3-5 minutes over medium heat.
Add spinach, soy sauce and sherry increase heat and cook until all the liquid has evaporated, remove from heat and stir in the cilantro, taste and adjust seasoning.
Place 1 teaspoon of the spinach mixture in the center of the wrapper, brush the edges of the wrapper with the cornstarch and water mixture.
Fold the wrapper diagonally over the filling to form a triangle, firmly press the edges together to seal.
Join the two bottom edges of the triangle together and seal.
Then repeat until all the mixture is used.