- Preheat the oven to 200C. Lightly oil a 20cm square glass dish, pan, or silicon cake tin.
- Squeeze the water out of the potato and drain on paper towel. Heat the butter and oil in a frypan and cook the potato, turning often until it starts to brown. Press into the bottom of the square tin and place in the oven while you prepare the bacon.
- Fry the bacon lightly and place over the potato.
- Lightly beat the eggs, add sage and salt and pepper then mix in one cup of the cheese and the spinach. Pour evenly over the bacon and potato and place back into the oven.
- When the eggs are almost cooked (about 10 -12 minutes) sprinkle on the remaining cheese and leave in the oven to melt for a few more minutes. Or you can use the grill to brown the top. Cut into squares and serve warm as breakfast or brunch. It is also great cold as a picnic slice for lunch.