Stuffed portobello mushrooms

This dish was another culinary experiment - I got these beautiful portobello mushrooms and was wondering what to do with them. I've decided to stuff them with some of the things I already had in the fridge and it turned out delicious!
It's a food that doesn't need much preparation, a little bit of frying, then stuck in the oven and wait for it to be ready, so it's a good idea for a dinner when you don't have so much time!

INGREDIENTS (for 4 servings):

•  4 portobello mushrooms
• 2 green bell peppers
• 1-2 pork sausages
• 1 big onion
• 1 egg
• 1 lemon
• 4 slices of cheese (gouda in my case)
• 1-2tbs olive oil for frying
• oregano, salt, pepper to taste

Cut out the "legs" of mushrooms (you may also remove some of the insides to create more room for the filling). Preheat a pan with olive oil.
Finely chop the onion and fry until slightly golden, then add sausages cut into small cubes and chopped peppers. Sprinkle with salt, pepper and oregano. Fry for about 10 minutes and then set aside to cool down a little bit. If you want to save time, put the filling in a bowl and place it in another one filled with cold water.

Brush a baking pan with some olive oil and preheat the oven to 200°C (392°F). When the filling gets cool, mix in the egg - this will make stuffing stick together after it's cooked.
Fill up mushroom caps with the stuffing using a spoon and place them on the baking pan. Sprinkle with some oregano and lemon juice, place lemon in the middle and bake for about 15-20 minutes, until they're soft.

Take your mushrooms out, place a slice of cheese on each one and put it back in the oven for few more minutes to melt the cheese.

Serve hot with extra lemon and fresh bread.

Enjoy!