Rhubarb bran muffins

Name: Rhubarb bran muffins
Prep time: 30 min
Cook time: 30 min
Total time: 1 h
Cuisine: European
Ingredients: 250.00 ml oat bran; 187.50 gm boiling water, plus 1 tbsp extra; 6 stalks rhubarb, trimmed, chopped; 118.80 gm brand brown sugar; 1 egg, lightly beaten; 36.80 gm vegetable oil; 150.00 gm self-raising flour, sifted; 64.38 gm milk