Combine flour, salt, and pepper in a large resealable plastic bag; add 1/2 of the chicken and shake until pieces are thoroughly coated. Remove chicken, shaking off excess flour. Repeat with remaining chicken.

Heat olive oil in a large skillet over medium heat; add 1/2 of the garlic. Working in batches, add chicken, skin-side down; cook until browned on all sides, about 10 minutes. Transfer chicken to a Dutch oven. Repeat cooking with remaining chicken.

Preheat oven to 350 degrees F (175 degrees C).

Cook and stir onion, remaining garlic, and bacon in the skillet used for chicken until onion is tender and bacon is crisp, about 10 minutes. Pour chicken stock into the skillet and bring to a boil while scraping the browned bits of food off of the bottom of the pan with a wooden spoon.

Mix beer, orange juice, thyme, and parsley into onion-bacon mixture until combined; pour over chicken. Cover Dutch oven.

Bake in the preheated oven until chicken is very tender, about 1 hour. An instant-read thermometer inserted into the thickest part of the thigh, near the bone should read 165 degrees F (74 degrees C).

Transfer chicken to a serving platter and cover with aluminum foil. Place Dutch oven on the stove and cook over medium heat until gravy is reduced and thickened, about 5 minutes. Strain herbs out of gravy and serve gravy alongside chicken.