Season the chicken on either side with salt. Start by bring a large frying pan to a medium-high heat. Add olive oil and season chicken breasts, once the chicken has browned on one side, flip and repeat. Remove once browned and set aside to rest.
In the same frying pan, no need to clean, add butter, garlic and thyme. Once bubbly and fragrant, add flour and stir. Once the mixture starts to become toasty and golden in colour, gradually add warm milk and chicken stock while whisking. Continue whisking until the mixture starts to thicken and there are no lumps left. Add the cream, fresh lemon juice, and Dijon mustard. Whisk until well combined.
Meanwhile, shred the rested chicken filets, once the white sauce is ready, add the shredded chicken and any remaining juices. Stir and season to taste with salt and pepper.
Serve with rice, mash, or pasta. Enjoy!