Start by making the waffle batter. Mix together the flour, cornflour, baking powder and salt in a large bowl. Add the buttermilk, oil and egg yolks and mix until smooth. Whisk the egg whites together in a separate bowl until stiff peaks form. Add the egg whites to the rest of the ingredients and stir together gently until combined.
Stir the chorizo, spinach and feta into the waffle batter. Cook a ladleful of the waffle batter at a time in your waffle maker according to the appliance instructions. The waffles should come out brown and a little crispy.
While the waffles are cooking heat a frying pan with a little oil over a medium-high heat for a couple of minutes until the whites are cooked and the edges are crispy. Top the waffles with an egg per person and a sprinkling of salt and pepper to serve.