Bica mantecada with corn flour

Ingredients

• Bica:
• 180g butter
• 450g sugar (I only added 400 and I found it sweet enough)
• 8 eggs
• 250g corn bread dough
• 250g mixture of strong white flour and corn flour, 50%
• Lemon zest
• Corn bread dough:
• 700g mixture of bread white flour and corn flour, 50%
• 450ml tepid water (mine was at 25°C)
• 1 package dried baker's yeast
• 2 tsp sea salt