Cut chicken breast into 1 inch bite size pieces, season with salt and pepper. Take out tough ends of asparagus and cut into 2 inch pieces. Thinly slice leeks, use only the white/light green parts. Mince cloves of garlic. Juice the lemon, should result in about 3 tbsps, but set aside a tiny amount for seasoning. Zest the lemon, chop fresh parsley. Crumble the Boursin cheese.
Head into a large skillet with 1 1/2 tbsps olive oil over medium/high heat. Add seasoned chicken pieces and cook, stirring occasionally, for 5-6 until lightly browned on the outside. Remove chicken to a plate. Into same skillet, add the asparagus pieces. Cook asparagus for 6-9 minutes until just nice and crunch. Season with salt, pepper and freshly squeezed lemon juice. Same as chicken, remove to its plate.
Turn medium/low heat and add some 1 1/2 tbsps extra virgin olive oil to the same skillet you just used. Add the sliced leeks and cook stirring for 5 minutes, until tender. Add the garlic and red pepper flakes and cook for a minute more whilst mixture bubbles fragrantly.
Add orzo to the skillet with the leek mixture, stirring continually cook again for 3-4 minutes until lightly browned. Add the chicken broth and water and stir until combined. Gently bring the mixture to boil and then drop to a medium heat and simmer for about 10-12 minutes.
Add seared chicken, asparagus from step two to skillet with crumbled Boursin cheese. Stir gently until cheese is melted in, season with salt and pepper - then taste with lemon juice. Garnish with parsley and zest if desired.