Preheat oven to 160c (320F).
Add biscuits, protein powder and cinnamon to a food processor and blend for 10-30 seconds. Add melted butter and milk (1/2 tbsp at a time) and mix until a slightly sticky crumble forms.
Pour the base into a brownie pan lined with parchment paper, and using the back of a spoon or your hands, pat down until even. Bake for 10 minutes and let cool.
Mix the Cinnamon Roll filling ingredients until a slightly sticky filling forms (don't want it too wet, add extra protein powder if needed), and set aside.
Add cream cheese, yogurt, eggs and vanilla into a medium bowl and whisk by hand or an electric hand mixer until well combined. Add the dry ingredients and whisk until just combined, do not over-mix.
Pour half the cheesecake batter on the cooled base and sprinkle half the cinnamon roll filling on top. Add the rest of the batter and swirl the rest of the cinnamon roll filling on top. I like to sprinkle some of the cinnamon filling then swirl and then repeat.
Optional Bain Marie: place pan into a larger baking dish or pan filled with hot water, making sure that the water level comes up about 1 inch on the sides of the pan.
Bake for 30-40 minutes (30 is more creamy, 40 is more firm).
Let the cheesecake cool completely before refrigerating for a minimum of 5 hours.
Cut into 12 equal slices and enjoy.