In a medium bowl, combine the dry ingredients.
Add the warm milk, vanilla and roux to the bowl of a stand mixer fitted with the hook attachment. Then add the dry ingredients.
Turn the mixer on medium-low and mix for 5-7 minutes until gluten develops and the dough feels elastic.
Add the butter one tablespoon at a time and wait until it's fully incorporate before adding more. Mix for another 5-7 minutes until the butter is completely incorporated and the dough is smooth and feels elastic.
Transfer to a greased bowl. Cover and let rise for about 2 hours or until doubled in size.
While the dough is resting, make the filling.
After the first raise, gently deflate the dough on a floured surface and using a rolling pin, roll the dough out into a rectangle (roughly 30×50 cm). The shorter side should not be more than 3-5cm longer than your loaf pan.
Spread the filling over the flattened dough and sprinkle over the raisins and pecans evenly. Press to make them stick to the spread.
Starting from the short edge, roll the dough into a log, keeping it fairly tight as you go. When you reach the edge, pinch along the edge to seal.
Using a sharp knife, cut the log in half lengthwise and twist the two logs around each other leaving the filling exposed.
Transfer to a greased and parchment-lined loaf . Cover and let rise in a warm place for 45 minute.
Preheat oven to 175C | 350F degrees and bake for about 25 minutes or until the top is golden brown.
Once baked, remove from the oven and allow to cool completely before slicing and eating.