In a 1-quart, heat proof, microwavable measuring bowl, mix all of the ingredients. Heat in the microwave on high for about 5 minutes or until the butter is completely melted. Stir and heat until mixture is reduced to 1 1/2 cups, about 10 minutes. Let stand at room temperature for about 30 minutes until slightly thickened.
Hints for success: - Be sure to heat the griddle before pouring your pancake batter. - Using a copper bowl to whisk the egg whites will give you more volume. - Do not whisk the whites until they appear dry. They should be stiff, yet moist. - Fold the whites and the squash mixture gently. If you over do it you will deflate the whites and have tougher, flatter pancakes. - The syrup is rich and full of flavor. You can make it the night before, refrigerate it and reheat the next morning. - Use the freshest apple cider you can find. If you use apple juice, try to use one that is not overly sweet.