How to Make It
Rub the chicken with the garlic and 1 tablespoon of kosher salt. Cover and refrigerate for 1 hour.
Heat the olive oil in a large, deep skillet. Scrape the garlic off of the chicken pieces. Add the chicken to the skillet in a single layer and cook over moderately high heat, turning occasionally, until browned all over, about 12 minutes. Transfer the chicken to a platter.
Add the onion to the skillet and cook over low heat, stirring occasionally, until very tender, about 10 minutes. Add the piquillo peppers and white wine and bring to a simmer, scraping up any browned bits.
Return the chicken and any accumulated juices to the skillet. Cover partially and cook over low heat until the chicken is tender and cooked through and the sauce is thickened, about 30 minutes. Transfer the chicken to a platter, spoon the sauce on top and serve.