Can i substitute Nesquik for cocoa powder?
No. The Nesquik has fillers, is pre-sweetened and does not have the same amount of cocoa powder, teaspoon to teaspoon as cocoa powder would. You would have to diddle the recipe quite a bit to reduce your sugar. you could try substituting the Nesquik entirely for both the sugar and the cocoa powder measurement in the recipe – but I do not suspect it will have desired results.