01 - Season both sides of the chicken breasts with salt, pepper, and garlic powder, ensuring even coverage.
02 - Heat olive oil and butter in a large skillet over medium-high heat. Add chicken and sear for 4-5 minutes per side until golden brown and nearly cooked through. Transfer to a plate and reserve.
03 - Reduce heat to medium. Add chopped shallot and garlic to the skillet; sauté for 2-3 minutes until softened and fragrant.
04 - Pour in chicken broth, scraping up browned bits from the bottom. Simmer for 2 minutes to concentrate flavor.
05 - Stir in heavy cream, Dijon mustard, and chopped dill. Bring to a gentle simmer, stirring constantly to incorporate.
06 - Return chicken and accumulated juices to the skillet. Simmer on low heat for 6-8 minutes until chicken is fully cooked and sauce has thickened to coat the back of a spoon.
07 - Stir in lemon juice and adjust seasoning as needed. Garnish with additional fresh dill and serve immediately.