A day before cooking, rinse the chicken inside and out under cold water and pat dry. Salt it liberally, cover and refrigerate.
Remove the chicken from the refrigerator an hour before cooking it.
Preheat oven to 425°F.
Lift the skin off each chicken breast and wedge 3 lemon slices and a bay leaf between the skin and each breast. Put the onion, garlic, thyme and remaining lemon in the cavity of the chicken. Rub the entire chicken liberally with the olive oil. Put the chicken in an ovenproof sauté pan or in a roasting pan breast side up, slide it into the oven and roast it until the thigh reaches 160°F or until the cavity juices run clear, about 1 hour.
Remove from the oven and let rest for 10-20 minutes.
For the Salsa Verde, combine the extra-virgin olive oil, parsley, capers, mint, red pepper flakes, anchovies, garlic, lemon zest and juice, jalapeño and shallots in a bowl, and stir to combine. Add salt and pepper to taste.
Cut the chicken into 8 pieces and serve with the salsa verde.