Grease a 9-inch round cake pan and set aside.
In a small bowl, mix together the ground flax seed, water, olive oil, yeast, and sugar. Let sit for 5 minutes.
In a large bowl, whisk together the flour and baking powder, add the yeast mixture, chocolate chips, vanilla, coffee, and salt. Stir together until the dough starts to form.
Transfer dough to prepared pan and loosely cover with a kitchen towel. Allow to rise at room temperature for 60 minutes.
When the dough is almost done rising, preheat oven to 350°F.
Bake for 25-30 minutes. Allow to cool for 10 minutes. Drizzle caramel sauce over cake before serving.