For icing: In small saucepan, melt chocolate and 1 tablespoon butter over low heat. Remove from heat and, with electric mixer, beat in icing sugar and 2 tablespoons hot water. Beat until smooth. Drizzle over filled eclairs.
For shells: In medium saucepan bring 1 cup water to a boil, stir in 1/2 cup butter and salt. Stir until melted. Add flour all at once and stir vigorously until mixture forms a ball. Remove from heat and beat in eggs, one at a time, until smooth. Drop by tablespoons onto baking tray.
Bake 15 minutes in the preheated oven, then reduce heat to 190 degrees C (375 degrees F) and bake until golden, 10 to 15 minutes. Cool completely.
For filling: In large bowl, beat 1/2 cup of milk, a little at a time, into softened cream cheese, until creamy. Beat in remaining 1 1/2 cups milk and pudding mix. Stir until thick, 1 to 2 minutes. Cut tops off cooled pastry shells and fill. Replace tops.