• Preheat your oven to 220°C/200°C fan/gas mark 7.
• Trim the parsnip then quarter lengthways. Chop widthways into small pieces. Chop the sweet potatoes into 2cm chunks (peeling optional).
• Roughly chop the mushrooms.
• Trim the root and the dark green leafy part from the leek. Halve lengthways, then thinly slice.
• Peel and grate the garlic (or use a garlic press). Pick the thyme leaves (discard the stalks).

• Place a large pot over medium-high heat with a drizzle of oil.
• Once hot, add the mushrooms and leek.
• Fry until browned, 5-7 mins. Season with salt and pepper.
• Add the parsnip, sweet potato, garlic and thyme.
• Cook, stirring, 2-3 mins.

• Stir in the stock, passata, 350ml water and ½ tsp sugar (double both for 4p).
• Cover the pot and simmer until the sweet potato and parsnip are fork tender, 15-20 mins.

• Meanwhile, halve the baguettes lengthways. Cut each half into four equal triangles.
• Pop onto a lined baking tray and toast until golden brown, 2-3 mins.
• Once golden, remove the crostini from the oven and scatter over the cheese.
• Return to the oven until the cheese has melted, 1-2 mins.
• Roughly chop the parsley (stalks and all).

• In a small bowl, mix together 1 tsp flour and 2 tsp water (double both for 4p).
• Once the stew has simmered, stir the flour mixture into the stew. 
• Cook until the stew is slightly thickened, another 3-5 mins.
• Season to taste with sugar, salt and pepper. 

TIP: Add a splash of water if you feel the stew has become too thick.

• Divide hearty helpings of your stew between bowls.
• Serve with the cheesy crostini on the side.
• Garnish with a sprinkling of parsley.