For the best flavor, use high-quality chocolate. Consider using couverture chocolate for a superior shine and snap. Ensure the egg whites are beaten to stiff peaks for a light and airy cake texture. When melting chocolate, avoid overheating to prevent it from seizing. Stir frequently and use a low heat setting. The cake bites can be stored in an airtight container at room temperature for up to 3 days, or in the refrigerator for up to a week.