Mix all solids in a food processor (sugar, trehalose, flour, baking powder, salt, nutmeg and lemon zest).
Add eggs, banana puree, rum and vanilla extract.
Heat butter up to 60ºC and add to the mixture.
Fill a buttered and floured stainless steel frame with the batter up to 40% capacity.
Arrange diced banana and minced pecan nuts on the dough.
Finish filling with the batter up to 65% of the mould capacity.
Bake at 180ºC for 20 minutes.
After 8 minutes, cut the centre with the help of a knife dipped in water and bring back to the oven to finish baking.
Once the cakes are cooked, perfect the shape and set aside.