Sprinkle both sides of chicken tenders with 1/4 tsp. each thyme, salt and pepper.
Heat 1 Tbsp. oil in a large skillet over medium-high heat. Reduce heat to medium and add the chicken. Cook, stirring, for 3-4 minutes until lightly browned on all sides. Transfer to a clean plate.
Add the remaining 1 Tbsp. oil to the pan. Add apples, onion, 2 Tbsp. cider (or juice) and the remaining 1/2 tsp. each thyme and salt. Stir to combine. Cook for 3-4 minutes, stirring often, until the apples and onion are softened.
Add cranberries and sprinkle flour over everything in the pan; cook, stirring, for 1 minute.
Return the chicken to the pan and pour in the remaining cider (or juice). Cover and cook about 3 minutes more, stirring once or twice, until the sauce has thickened and the chicken is cooked through.