Combine flour, suet, raisins, corn syrup, water, 1 teaspoon salt, baking soda, cinnamon, baking powder, nutmeg, and cloves in a large bowl; mix until well combined.
Transfer pudding batter into a large mold or double boiler and steam over 1 inch of hot, but not boiling, water. Steam until a toothpick inserted comes out clean, about 1 to 1 ½ hours.
To make the sauce: Combine milk, sugar, cornstarch, butter, and remaining 1 teaspoon salt in a medium saucepan. Warm over medium heat, stirring constantly until mixture thickens; stir in vanilla extract.