In a stand mixer combine flour, eggs, sugar, salt, instant yeast, milk/buttermilk, vanilla, and cinnamon for the bread dough, adding pieces of cream cheese one at a time until dough forms and pulls away from the sides of the bowl. If the dough seems too dry add one tablespoon more water, if it's too wet add add a bit more flour, one tablespoon at a time.
Grease a large bowl with butter or oil and place dough in it, turning it over a couple of times to coat the surface with oil. Cover, and let rise in a warm, non-drafty place for 60-90 minutes until doubled in size.
Once the dough has doubled in size, turn dough out onto a floured surface. Using a floured rolling pin, roll the dough out into about a 15x18 inch sheet. It doesn't need to be exact.
Preheat oven to 350 degrees.
To create the swirl, sprinkle rolled out dough evenly with brown sugar, then cinnamon, roll it up, and place it seam side down on a baking sheet. If necessary, cut it in half to make two shorter loaves.
Let the uncooked loaves go through a second rise, for about one hour (can take anywhere from 30-90 minutes) lightly covered with plastic wrap.
Bake for 20-24 minutes, until golden brown. Remove from oven, and let cool enough to handle.
Slice evenly into about 1-inch thick slices.
Preheat griddle to 375 degrees. Whisk the 8 eggs, vanilla and cinnamon until combined.
Begin to dip each piece of swirl bread into the egg mixture and transfer straight to the griddle. Grill on one side until it is completely golden brown (about 4 minutes) before flipping over to repeat on the other side.
Working in batches, repeat until all of the pieces of French toast are grilled. Serve with butter, syrup, or toppings of choice. Leftovers freeze well for easy reheat.