Step 1: Combine eggs, sugar, vanilla, cinnamon, lemon zest, milk, bread, and butter in a bowl. Let the bread soak in the mixture.
Step 2: Cover and rest for 15 minutes. Stir occasionally for even soaking.
Step 3: Dissolve sugar, water, and lemon juice until smooth. Coat the pudding pan by pouring caramel inside.
Step 4: Bake at 350°F for 50-60 minutes in a water-filled larger dish until golden and clean toothpick test.
Step 5: Cool, invert onto a platter, and serve with favorite toppings or drizzle with caramel sauce. Enjoy!