Preheat oven to 450°F. LIghtly grease a large cookie sheet and set aside.

In medium saucepan, combine ½ cup butter and water. Bring to a boil, stirring to melt butter.

Reduce heat to low and stir in flour and salt with a wooden spoon until the mixture begins to form a stiff ball of dough.

Remove from heat and add eggs, one at a time, stirring vigorously after each addition to ensure they are incorporated. Work quickly, especially with the first one, to prevent it from cooking into scrambled eggs on the bottom of your warm pan :)

With a spoon or pastry bag fitted with a large tip, spread/pipe the thick dough onto prepared cookie sheet into 10 strips approximately 1½ x 4" each.

Bake for 15 minutes, then reduce heat to 325 and bake another 20 minutes, until puffed and golden and hollow sounding when lightly tapped on the bottom. When removed from oven, IMMEDIATELY pierce the ends almost through to the other side to let steam escape and prevent any sogginess in the middle. This hole is also where you will be piping your filling into. Let cool completely before filling and icing (this will only take about half an hour).

For CUSTARD FILLING: combine pudding and milk in a bowl and mix according to package directions. In a separate bowl, beat the heavy cream with an electric mixer until soft peaks form. Beat in ¼ cup icing sugar, 1 tsp vanilla, and ¼ tsp salt. Fold whipped cream into pudding.

Scoop mixture into pastry bag fitted with a smallish tip (I enlarged my steam holes a bit to make my tip fit, so do whatever works) and pipe mixture into centers of eclairs until full. This is a bit of a messy business, but worth it for ease of eating and pretty appearance. You could certainly also just slice the eclairs in half horizontally, fill the bottoms with cream, and replace the tops. Either way, you will probably have some custard leftover.

For ICING: Melt the chocolate and 2 Tbsp butter over low heat in a saucepan (or in the microwave, stirring after 30 seconds and giving additional 10 second increments as needed until fully melted). Stir in 1 cup icing sugar and 1 tsp vanilla. Stir in hot water, 1 Tbsp at a time, until icing is smooth and reaches desired consistency. Drizzle, pipe or spread over filled eclairs.

Store in the fridge.