Sweet potato and jalapeño scones with gravy and maple mushrooms

Method

1. Heat the oven to 180°C/160°C fan/gas 4. For the maple-grilled mushrooms, mix the maple syrup, olive oil, tamari or soy sauce, garlic, thyme and mustard powder in 
a large bowl, add the portobello mushrooms and toss to coat. Cover with cling film and leave to marinate at room temperature for 30 minutes.
2. Meanwhile, make the biscuits: toss the sweet potato in the oil in 
a bowl, spread out on a baking tray and roast for 15-20 minutes or until tender. Remove and leave to cool.
3. Increase the oven temperature 
to 220°C/200°C fan/gas 7 and line 
a baking tray with baking paper.
4. Sift the flour, baking powder and bicarbonate of soda together in 
a bowl, then add the sugar, salt, suet and margarine and mix to combine. Using your fingertips, rub the suet and margarine into the flour for 7-8 minutes until incorporated and the mixture resembles breadcrumbs.
5. Add the cooled sweet potato, jalapeños and yogurt, then mix together to form a ball. Transfer 
to a lightly floured work surface and use your palm to fold the dough onto itself a few times.
6. Pat out the dough to about 1.5cm thick. Use the floured cutter to cut out 8 biscuits, re-rolling the scraps and dusting the cutter with flour each time. Put the biscuits on the lined tray, touching slightly as this will help them rise uniformly.
7. Brush the tops of the biscuits with melted margarine and bake for 15-18 minutes until risen and golden. Put on a wire rack to cool for 10-15 minutes. Turn the oven down to 180°C/160°C fan/gas 4.
8. Meanwhile, make the gravy. Melt the margarine in a saucepan, then add the shallots and garlic and cook gently for a few minutes, stirring frequently until they have softened. Add the chestnut mushrooms and cook over a medium-high heat for 3-4 minutes, stirring, until browned.
9. Add the flour and mix in well, then stir in the remaining ingredients. Cook, stirring constantly, until the gravy has thickened (6-8 minutes). Season to taste and keep warm.
10. Heat a griddle pan until hot, then add the marinated mushrooms in batches and cook for 3 minutes on each side, transferring to a baking tray in the oven while you cook the others. Bake in the oven for a further 5-10 minutes until softened.
11. To serve, cut each biscuit in half and serve with a maple-grilled mushroom and a large spoonful of gravy. Serve with sautéed spinach too, if you like.