You can manage multiple restaurants by switching between them using the 'My Restaurants' tab on the main menu. Each restaurant has its own set of dishes and customers, so ensure you allocate enough time and resources to each one.

Unlock new recipes by completing levels or achievements. As you progress through the game, you'll gain access to more dishes and cooking techniques. Check your recipe book regularly for updates.

To upgrade kitchen equipment efficiently, prioritize upgrades based on usage frequency and efficiency gains. Focus on equipment that will help you cook faster or serve customers quicker, which can be found in the 'Kitchen' section of the app.

Improving customer satisfaction involves quick service, delicious food, and personalization. Use the 'Customer Satisfaction' meter as a guide. Cook dishes according to their preferences, serve them promptly, and offer additional items like drinks or desserts to enhance their experience.