Preheat oven to 200°C. Line a 26 x 16 x 3 cm lamington tin with baking paper. Sift the flour into a large bowl. Using your fingertips, rub the butter into the flour until the mixture resembles breadcrumbs. Make a well in the centre and add the buttermilk. Stir with a flat-edged knife until well combined and a soft dough is formed.
Turn out dough on a lightly floured surface and knead quickly but gently until smooth. Roll out dough on a lightly floured surface to a 1 cm-thick rectangle, measuring 36 x 21 cm. Sprinkle sugar over top of dough. Top with pecans and dot with extra butter.
Carefully roll up dough from the longest side. Using a large sharp knife, cut through the roll to form 12 rounds. Put the rounds close together in the prepared tin. Bake for 15-20 minutes or until crisp and well browned. Transfer to a wire rack to cool. Brush each muffin with Caramel glaze.
To make Caramel glaze: Put the butter, sugar and water in a medium heavy-based pan and stir to combine. Simmer, stirring, for 3-4 minutes or until the mixture is smooth and the sugar dissolves.