In a large pan, heat olive oil and chilli flakes. Add in leeks and garlic. Saute on medium high for several minutes until leeks start to soften.
Add in mushrooms. If you have a cover for the pan, cook mushrooms for several minutes, shaking the pan frequently. Season with salt and pepper.
Once mushrooms are cooked remove everything from the pan, place into a bowl and set aside. Place the pan back on heat and deglaze with vinegar and water (or wine if using).
Add rice to the pan and give the pan a good shake. All the bits of leek, garlic and oil will coat the rice. Leave rice alone for a couple of minutes to “toast” the rice.
Use a ladle to add broth. Add two ladles of hot broth to rice. Toss to coat, stirring frequently. Once the broth has almost fully absorbed the rice, add another ladle.
Keep going until the broth is finished and rice is cooked (al dente).
Add mushrooms and leek mixture back to the pan. Add frozen peas and spinach.
Cover risotto to allow the spinach to wilt and peas to heat through.
Add lemon juice, season with olive oil, more cheese, salt and pepper!