Cut the red pepper and zucchini into fine strips. Mince the garlic clove.
Heat roughly 2-3 tablespoons of oil in a large pan over medium-high heat. Season the chicken breasts with salt and pepper.
Fry the chicken breasts for about 15 minutes, turning occasionally, until cooked through (74°C / 165°F internal temperature). Remove and set aside on a warm plate.
In the same hot pan, add the minced garlic and fry for 1-2 minutes until fragrant.
Add the red pepper strips, zucchini strips, and sugar snap peas. Cook for about 5 minutes, stirring occasionally, until the vegetables are soft.
In a small bowl, mix the cornstarch with the chicken stock. Pour the mixture into the pan. Add ½ teaspoon thyme and season with salt and pepper.
Heat while stirring constantly until the sauce thickens, about 2-3 minutes. Let simmer for 2 minutes.
Return the chicken breasts to the pan and heat through for about 1 minute. Add a handful of fresh basil leaves and 3 tablespoons of freshly grated parmesan, stirring until the parmesan melts.