In a large shallow bowl, whisk together the eggs, whole milk, heavy cream, granulated sugar, ground cinnamon, vanilla extract, and salt. Continue whisking until the mixture is smooth and the cinnamon is evenly distributed.
Arrange the bread slices on a plate or cutting board. If the slices are especially fresh and soft, let them sit uncovered for a few minutes so they can absorb the egg mixture without becoming too soggy.
Take one slice of bread and dip it into the egg mixture, allowing each side to soak for a few seconds. Make sure both sides are coated, but avoid leaving the bread submerged for too long.
Place a large nonstick skillet or griddle over medium heat. Add a little butter and let it melt, coating the cooking surface evenly.
Place the soaked bread slices into the warm skillet without overcrowding. Cook for approximately 2–3 minutes on each side, until the surfaces are golden brown and the centers are cooked through.
Transfer the cooked slices to a serving plate. Add more butter to the skillet as needed and repeat with the remaining bread and egg mixture.
Arrange the cinnamon French toast on plates and finish with your favorite toppings. Maple syrup, powdered sugar, fresh berries, or an extra sprinkle of cinnamon all make lovely additions.