Healthy French Onion Dip - A better choice!

Ingredients

• 2 brown onions, thinly sliced
• 2 tbsp olive oil
• 1 tsp salt
• 1 tsp fresh thyme, chopped
• 2 tbsp balsamic vinegar
• 2 cloves garlic, minced
• 1 tbsp Worcestershire sauce
• 2 cups Greek yoghurt
• Salt & pepper, to taste