Crepes with Ham, Cheese and Spinach Filling

I am in the process of trying to use up stuff I have in my freezer so we had savory Ham, Spinach and Cheese crepes for dinner so that I could use the crepes we got from IKEA. They were good enough, but crepes should really be served fresh out of a hot, lightly buttered pan. It was a hit:

Crepes
via Julia Childs from Julia and Jacques: Cooking at Home by Julia Childs and jacques Pepin

Yields 12-15 crepes (7")

1 cup Flour, all purpose
2 Eggs, large (sometimes I have to use 3)
1 Egg Yolk
3/4 cup Milk
1/3 cup Butter, melted
2 TBS Sugar (I leave this out if I am making savory crepes)
A large pinch of Salt (I leave this out if I am using salted butter)
3/4 cup Water, warm

2 Tbs+ Butter, melted, for brushing the pan.

Filling:

1 Ham Steak, finely diced
4 slices Canadian Bacon, finely diced (optional)
10 oz. Spinach, thawed and squeezed to release extra liquid
1/2 cup mayonnaise
2 tablespoons Dijon mustard
1/2 - 3/4 cup Cheese (Swiss is best, but Cheddar works nicely, too) shredded

Instructions for the crepe batter
Add all ingredients to the work carafe of a blender, add the lid, and blend on HIGH for about 20 seconds. Stop the blender, scrape down the sides, replace the lid and pulse three more times. Put the blender carafe in the refrigerator and let rest for 30 minutes to 24 hours before proceeding.

To Cook Crepes:
Place a heavy-bottomed non-stick skillet, crepe pan or well-seasoned cast-iron pan over medium heat. Use a heat-proof pastry brush to lightly brush the pan with melted butter, taking care to get the edges of the bottom of the pan as that is where batter tends to stick.
Pour about 2-4 ounces of batter into the center of the pan and immediately tilt and swirl the pan so that the batter covers the entire bottom of the pan.
Set the pan back over the heat and let it cook until the crepe has no visible wet areas on top.
Use a semi-flexible spatula to run around the edges of the crepe before lifting and turning the crepe. Cook the second side for about 10 seconds only. The goal is just to lightly color that side.
Transfer the finished crepe to a cooling rack. Repeat until you have used all the crepe batter.

For Filling:
Lightly butter the bottom of a hot pan. Add in the bacon and ham. Heat until cooked through. Remove from pan, or at least push it to the side. Lightly butter the pan again and add the spinach. Cook until it is warm. Add in the mayonnaise and the Dijon mustard. Stir to mix and heat through.

To serve place the ham, spinach and sauce mix in a thin line down the center of the crepe. Add a bit of cheese and roll up. Heat up, if needed, before serving.
Serve hot.