Remove the stalks from the mushrooms and finely chop them.
Heat 1 tbsp olive oil in a large frying pan over low heat. Add the chopped stalks and garlic, cooking for 2 minutes until softened.
To wilt the spinach, add the spinach, cover and cook for 30 seconds, stir and remove.
Transfer the spinach mixture to a plate and spread out to cool. Once cooled, remove as much water as possible, then chop it and mix with the nutmeg, ricotta lemon zest, and salt and pepper to taste.
Take each mushroom and add a cross to the base, then spoon the ricotta mixture into each mushroom.
Top each mushroom with the panko breadcrumbs and grated parmesan over the filling.
Place the potatoes in the oven and set the mushrooms on a wire rack above them.
Cook for 30 minutes until the mushrooms are tender, the topping is golden, and the potatoes are crispy. Serve the stuffed mushrooms with potatoes, a handful of rocket and a dollop of tomato ketchup.
Tips
Extra Flavour: Add chopped soft herbs like parsley or chives to the ricotta filling if you have them on hand.
Customisation: For added texture, mix grated cheese into the breadcrumbs before sprinkling.