Warm Holiday Artichoke Spinach Dip

Ingredients
2 TBS olive oil
1 TBS butter
1 large onion, diced
2 cloves garlic, minced
2 TBS flour
1/2 cup broth (vegetable or chicken)
10 oz frozen spinach  
14oz can artichoke hearts, chopped
3/4 cup plain lowfat yogurt
1 cup parmesan
1/2 tsp cayenne
salt & pepper to taste
Directions
1. Melt butter with oil in a large pan over medium heat.
2.  Add onion and garlic. Saute about 6 min. until onion is tender.
3. Add flour and stir 1-2 minutes.
4. Stir in stock and cook 1-2 minutes until mixture thickens.
5. Reduce heat to low and stir in spinach, artichoke hearts, cayenne and salt & pepper to taste.
6. Remove from heat and slowly add in yogurt. To avoid curdling, mix a bit of warm veggie mixture into yogurt first and then add this mixture into saucepan gradually, stirring all the while.
7. Mix in cheese.
8. Transfer dip to a serving bowl and serve with favorite crackers, pita or tortilla chips. Carrot “chips” and celery are great too!
If needed, dip can stay warm on very low heat in oven until ready to serve. 
*adapted from Stonyfield.com