Often, it is just one simple ingredient that can take a baked good from tasty to Oh Lord This Is Great. Dairy is often present in cakes and muffins, so consider replacing cream or even buttermilk or sour cream with some home made crème fraîche.
Crème fraîche is rich and tangy and is higher in fat than sour cream. You might not want to use it if you are, or you are baking for someone who is, on a diet, but you will really appreciate the slight tang and richness and tenderness of crumb that crème fraîche provides.
Crème fraîche is available at gourmet markets, but it is very expensive. You can make your own by following this simple formula:
Crème Fraîche
For each cup of heavy cream, you will need two TBSP of buttermilk.
In a clean, lidded container, whisk together the cream and the buttermilk very well. Cover and place in a warm part of your kitchen. Check twice per day to see if the cream has thickened. This could take as long as 72 hours, depending on the temperature of your kitchen. When the cream has thickened and no longer "sloshes" in the container, refrigerate until ready to use.
This recipe scales very successfully, and if you needed to, you could make gallons of crème fraîche using the same ratio. For example, for two cups of heavy cream, use 1/4 cup of buttermilk. For every quart of heavy cream, use 1/2 cup of buttermilk.
To use crème fraîche in a recipe, substitute it one for one for any type of dairy called for in your recipe. If your crème fraîche is very thick, whisk it for a few seconds to thin it out some before adding it.
You can also use crème fraîche as a topping. It is particularly good as a topping for fruit pies, crisps and cobblers. Simply whisk cold crème fraîche with white or brown sugar to taste, a splash of vanilla and a pinch of salt. It will thin out initially, but then will whip up just like whipping cream. Whisk until you achieve desired thickness and then use as you would whipped cream or another whipped topping.