Dried Fenugreek leaves- can be found at the Indian store and is essential to the recipe. It wont taste like butter chicken without it. Toasting it brings out the flavor of the leaves.
Honey: I would add a tablespoon at a time and taste it because some honey are sweeter than others. We don’t want the sauce to be sweet but rather we use honey to balance out the acidity of the tomatoes. I use a local honey so I end up always using 3 tbsp which is perfect. Also avoid using floral honey in this recipe.