Preheat the oven to 350°F (175°C) and line a muffin tin with paper liners.
In a large mixing bowl, combine the pumpkin puree, brown sugar, vanilla extract, vegan yogurt and oil, stirring until the oil is no longer separately visible.
Sift in the all-purpose flour, baking powder, baking soda, cinnamon, cardamom, ground cloves, nutmeg, dry ginger, and salt. Stir until just combined. Be careful not to overmix.
If using the optional pistachio streusel topping, in a separate small bowl, combine the all-purpose flour, chopped raw pistachios, olive oil, brown sugar, cardamom, cinnamon, and salt. Mix until the mixture forms a crumbly texture.
Spoon the batter into the prepared muffin tin, filling each cup about three-quarters full. If using the pistachio streusel, sprinkle it evenly over the top of each muffin.
Bake in the preheated oven for 22-26 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Allow the muffins to cool in the tin for five minutes before transferring them to a wire rack to cool completely.
If using the optional rosewater cardamom glaze, whisk together the powdered sugar, vegan cream cheese, rosewater, unsweetened plant-based milk, and cardamom until smooth. Drizzle the glaze over the cooled muffins. Garnish lightly with sifted powdered sugar and dried rose petals before serving.