Ingredients:

1 pint heavy cream

2-3 tablespoons cultured buttermilk

Instructions

Gently stir the heavy cream and buttermilk together and leave in a warm spot (about 70-75F) for 12-24 hours, or until thickened. Refrigerate for 24 hours before using, and keep refrigerated from there on out. Use within a week or two. 

To make your crème fraiche extra fancy, add these extra ingredients after the crème fraiche has thickened:

• Lemon and Tarragon Crème Fraiche: Add the zest of one lemon and ¼ cup chopped fresh tarragon
• Dill Crème Fraiche: Add ¼ cup chopped fresh dill
• Chive Crème Fraiche: Add ¼ cup chopped fresh chives
• Spicy-Smoky Crème Fraiche: Add 1 tsp paprika, ¼ tsp white pepper, and a pinch of cayenne 
• Scarborough Faire Crème Fraiche: Add ½ TBSP fresh chopped parsley, ½ tsp fresh finely chopped sage, ½ tsp fresh finely chopped rosemary, and ½ TBSP fresh chopped thyme
• Chipotle Crème Fraiche: Add 1 minced chipotle pepper in adobo sauce and a pinch of cumin
• Cilantro-Lime Crème Fraiche: Add 1 TBSP chopped fresh cilantro and the zest of one lime