Hi LizC7, I have a Nutribullet and just love it. I do make my own "banana icecream". I use almond milk or coconut milk, 1/2 banana (sliced), then I add banana Casein (protein powder); it makes a delicious icecream-type dessert that is healthy and delish.
I usually just throw in different fruits with the spinach - always tasty. I did find that using blackberries, you're going to have lots of seeds - it didn't pulverize the seeds but it gives it a really nice purple color and it taste great.
Oh and Happy Birthday!!!