Chocolate-Covered Cannoli Cake

Ingredients

• 1 (18 1/4 ounce) package yellow cake mix
• 3 eggs (or as called for by your cake mix)
• 13 cup oil (or as called for by your cake mix)
• 1 13 cups water (or as called for by your cake mix)
• 2 teaspoons orange zest, divided
• 1 cup pistachios, shelled and finely chopped, divided
• 1 (15 ounce) container ricotta cheese
• 1 (8 ounce) container mascarpone cheese
• 1 cup confectioners' sugar
• 13 cup semisweet mini chocolate chips
• 2 (16 ounce) cans chocolate frosting
• chocolate shavings (optional)