Preparation

Preheat oven to 400°F. Put the butter into the blender jar. Set timer for 5 minutes and temperature on Medium. Once butter has melted add the onion. Cover the blender jar and stir, using quick bursts to break up. Let sauté, stirring occasionally. When time expires, allow mixture to cool for about 5 minutes. While cooling, divide the shredded zucchini among 6 ramekins. Top with the feta, again, evenly divided between each one. Once the onion has cooled, add the cream, eggs, salt and pepper. Blend on speed 2 for 20 seconds. Pour evenly over zucchini and feta in ramekins. Put ramekins on a rimmed baking sheet; bake in preheated oven for about 35 minutes, or until a knife when inserted into custard comes out clean.