Easy Chicken and Dumplings - A Duck's Oven

Ingredients

• 1/2 yellow onion (diced)
• 2 carrots (peeled and diced)
• 4 celery stalks (diced)
• 3 tbsp butter (divided)
• 1/4 cup flour
• 2 cups milk
• 1/2 tsp salt
• 1/2 tsp black pepper
• 1 tsp Italian seasoning
• 2 1/2 cups chicken stock
• 1/2 can store bought biscuit dough
• 2 cups cooked and chunkily shredded chicken