Season the chicken breast evenly on both sides with the sea salt and black pepper.
Heat the extra virgin olive oil in a large skillet over medium-high heat until shimmering.
Place the chicken in the skillet and sear for 3-4 minutes per side until a deep golden-brown crust forms.
Remove the chicken from the pan and set aside on a plate.
In the same skillet, add the diced yellow onion and trimmed green beans, sautéing for 3 minutes until the onion is translucent.
Stir in the minced garlic and halved cherry tomatoes, cooking for 1 minute until the garlic is fragrant and tomatoes begin to soften.
Pour in the chicken broth and return the chicken breast to the skillet, nestling it among the vegetables.
Reduce the heat to low, cover the skillet with a tight-fitting lid, and simmer for 8-10 minutes until the chicken is cooked through and the beans are tender.
Remove from heat, stir in the fresh lemon juice and thyme, and serve immediately while hot.