Place sultanas, sugar, butter, eggs, milk and vanilla in a large heavy bottomed saucepan. Cook over medium heat, stirring frequently until mixture is hot, slightly thickened and just beginning to bubble; about 4 to 5 minutes. Cool slightly uncovered in the refrigerator while continuing with recipe.
Preheat oven to 180 degrees C. Grease 12 muffin cups or coat with cooking spray.
Stir flour with baking powder, bicarb soda and salt in a large mixing bowl. Make a well in centre and pour in warm sultana mixture stirring just until combined. Stir in nuts until evenly mixed.
Spoon batter into muffin cups.
Bake in the centre of the preheated oven until golden and a cake tester inserted into centre of a muffin comes out clean; about 15 to 17 minutes.
Remove from oven and immediately pour about 1 teaspoon maple syrup over each muffin. Cool muffins in cups for 10 minutes then remove to a rack. Serve warm.