Step 1

Preheat oven to 325 degrees. Prepare six 6-oz. individual ramekins by coating sides and bottom with butter then sprinkling with some sugar. Set aside.

Step 2

In a large mixing bowl, combine egg yolks, buttermilk, lime zest and lime juice, mixing well.

Step 3

Add flour, sugar and salt and continue mixing until combined.

Step 4

In small bowl, beat egg whites until stiff peaks form.

Step 5

Fold beaten egg whites gently into egg-lime mixture.

Step 6

Divide batter evenly between the prepared ramekins.

Step 7

Place all six ramekins in a pan large enough to hold them side by side.

Step 8

Fill the pan with water until it reaches halfway up the sides of the ramekins.

Step 9

Place in oven and bake 55-60 minutes.

Step 10

Remove ramekins from water bath and let cool on wire rack. When cool, sprinkle top with powdered sugar and store in refrigerator.