In a blender, combine warm water, milk, eggs, melted butter, all-purpose flour, sugar, and salt. Blend on high until the batter is smooth and well combined, about 30 seconds. Once blended, let the batter rest for 15-30 minutes at room temperature to improve the texture.

Heat a non-stick skillet over medium heat and add a small pat of butter to grease the surface. Pour about 1/4 cup of crepe batter into the skillet, swirling it to cover the bottom evenly. Cook for about 1 minute until the crepe's edges turn golden and lift easily, then flip and cook the other side for another 30 seconds. Transfer cooked crepes to a cooling rack.

In a non-stick pan, melt a little butter over medium heat. Crack the eggs into a bowl, whisk them until well combined, then pour into the pan. Stir gently with a spatula, cooking until the eggs are fluffy and slightly moist, around 3-4 minutes. Remove from heat and set aside.

Take a prepared crepe and lay it flat on your work surface. Spread a thin layer of Dijon mustard over the surface, then sprinkle with cheese, layer on the deli ham, and add a generous serving of scrambled eggs. Top with a bit more cheese before folding the crepe in half and then rolling it tightly to enclose the filling completely.

In the same skillet used for cooking the crepes, melt a bit more butter over medium-low heat. Place the rolled crepes seam-side down in the skillet and sauté for about 2-3 minutes, turning to ensure they’re heated through and golden on all sides. Serve your Egg, Ham, and Cheese Crepes warm.