Slow Cooker Pot Roast with Mini Potatoes

Ingredients

• 1–3 lb boneless chuck (or pot) roast, rinsed and patted dry
• 1 tsp Kosher salt
• ½ tsp freshly ground pepper
• 1 Tbsp vegetable oil
• 1 large onion, quartered
• 3 large carrots, cut into spears
• 15 mini red or white potatoes, halved
• 3 celery stalks, cut into spears
• 3 parsnips, cut into spears
• 1 tsp dried thyme
• 1 cup beef stock
• ½ cup red wine
• 1½ Tbsp all-purpose flour
• 3 Tbsp water