Heat 1 cup of the oat milk and add the quick-cook oats. Cook until softened, about 3–5 minutes.
Allow the mixture to cool completely.
Blend the cooked oat mixture with the remaining oat milk, avocado, spinach leaves, agave syrup, Medjool dates, pistachios, cardamom, and vanilla until smooth and creamy. Do not add the coarsely powdered pistachios yet.
Pour the mixture into an ice cream maker if available. Otherwise, freeze the mixture and blend it every couple of hours 2–3 times to reduce ice crystal formation.
Dust the inside of popsicle molds with the coarsely powdered pistachios.
Fill the molds with the kulfi mixture and freeze for 4–6 hours, or until completely set.