Broccoli: If you don't have broccoli, you may add an equivalent amount of riced cauliflower which will work perfectly as well!
Vegan Feta: If you are not vegan or dairy free, use regular feta cheese or even goat cheese.
Walnuts: Another great substitute would be sliced almonds or pecans!
Pickled Beets: I have not making this with regular canned beets, but it will make an adequate substitute. Just make sure you taste and adjust seasonings if needed. (Of course use pickled beets if you can!)
If you want to avoid using processed food, you can use around 1-2 small fresh beets /1 medium beet (about 1 cup) roasted beets. Instructions include:
Scrub your beets well. Wrap each beet individually with foil. Roast in 375F oven for 1 hour, or till tender. Allow it to cool slightly. Add to the blender to puree before adding in the chickpeas and broccoli.
Recipe by Unconventional Cooks at https://unconventionalcooks.com/2016/08/26/beet-hummus-with-vegan-feta-cheese-walnuts-gluten-free-oil-free-tahini-free/