sweet & white potatoes au gratin

Ingredients For sweet & white potatoes au gratin

• 1 lb

  sweet potatoes,washed thinly sliced
• 1 lb

  white potatoes,washed thinly sliced
• 1 Tbsp

  olive oil
• 1 c

  red onion,thinly sliced
• 2 clove

  garlic,minced
• 1/2 c

  red bell peppers,thinly sliced
• 1 Tbsp

  fresh thyme leaves
• 1 Tbsp

  all-purpose flour
• 1/2 c

  whole milk or (your choice of the milk your family is drinking)
• 2 lg

  eggs
• 1 c

  yogurt, low-fat, plain (again your choice of the plain yogurt your family is eating)
• 1/4 tsp

  salt
• 1/2 tsp

  black pepper
• 1/2 c

  parmesan cheese,shredded,(divided)
• 1/2 c

  sharp cheddar cheese,shredded,(divided)