Add the canned chickpeas, spinach, chickpea flour and salt to a food processor and blitz until combined. The mixture should stick together enough to form patties, if it doesn't add more chickpea flour.
Use an ice cream scoop to scoop the falafel on a baking tray lined with parchment paper. Press them a bit flatter and spray them with oil.
Bake them in the oven for about 30 minutes, carefully flipping them with a spatula after 20 minutes. They should be crispy on the outside and soft but not mushy on the inside.