Lemon, ricotta and zucchini loaf cake-Donna Hay. 150g butter,1 cup caster sugar, 4 eggs, lemon rind & juice, vanilla, 1 cup ricotta, 2 cup plain flour, 2 tea.baking powder, 2 cup grated zucchini. Plus 3/4 cup rolled oats to be spread over batter (in tin) before baking. Oven 180C - 55 minutes.