Melt butter and chocolate in a saucepan over low heat, 3 to 5 minutes. Stir in condensed milk and water. Pour in eggs slowly, stirring constantly. Cook and stir until well combined, 3 to 5 minutes. Remove from heat. Stir in pecans, vanilla extract, and salt. Pour into the crust.
Bake in the preheated oven until center is set, 40 to 45 minutes. Chill for 3 hours.