Baked Chocolate Almond Oatmeal

Name: Baked Chocolate Almond Oatmeal
Ingredients: 10 to 12 Medjool dates (about 7 ounces/200 grams), pitted; 1 orange, zested and juiced; 3 tablespoons (42 grams) unsalted butter; 1 1/2 cups (240 grams) steel-cut oats; 1/2 cup (50 grams) sliced almonds; 3 tablespoons (24 grams) ground flax seed; 1 large egg; 3 cups (750 milliliters) whole milk; 3/4 cup (175 milliliters) buttermilk or whole milk; 1/4 cup (30 grams) cocoa powder; 2 teaspoons vanilla extract; 2 teaspoons ground cinnamon; 2 teaspoons baking powder; 3/4 teaspoon kosher salt; Fruit and/or vanilla yogurt, for serving