Squash, Celeriac & Caramelised Onion Lasagne - a vegetarian feast!
Roasted Squash, Celeriac and Caramelised Onion Lasagne
Servings: 6
: 662 kcal
Author: Just Jo
For the squash and celeriac
  • 1.75 kg butternut squash one very large or two medium squashes should weigh about this amount
  • 800-900 g whole celeriac
  • 3 cloves of garlic
  • 2 bay leaves
  • A drizzle of olive oil
  • 25 g butter
  • 2 tsp dried sage
For the onions
  • 3 very large Spanish onions peeled and finely sliced
  • 1 tbsp butter + 1 tsp olive oil
  • 2 bay leaves
  • 2 tbsp dark brown sugar
  • 2 tbsp Marsala wine
  • Salt and pepper
For the white sauce
  • 2 tbsp plain flour
  • 2 tsp English mustard powder or 1 tsp Dijon mustard
  • 2 tbsp butter
  • ¼ nutmeg grated
  • 500 ml milk
  • 250 g ricotta cheese
  • Salt and pepper
  • 4-5 tbsp finely grated parmesan
For the pasta (optional – you can just buy approx 400-500g fresh lasagne sheets if you prefer)
  • 200 g tipo 00 flour
  • 75 g fine ground polenta cornmeal
  • 2 large eggs
  • 1 tbsp olive oil
  • Salt and pepper
  1. Preheat the oven to 180°C. Wash and scrub the butternut and celeriac very thoroughly. Place the squash on a baking tray but enclose the celeriac in a large piece of foil with the garlic, 2 bay leaves and a trickle of olive oil – close loosely around the root and place next to the squash. It has thinner skin than the squash and needs protecting to make sure it steams and softens, not dry out in the oven. Cook for 90 minutes until a small sharp knife can be plunged into both with no resistance. Leave until cool enough to handle. Reserve the garlic.
  2. Cut the squash in half and scoop out the seeds, discard them. Scoop the super soft flesh into a large bowl. For the celeriac, cut away the skin with a small sharp knife then break into chunks and place in a second large bowl. The celeriac will need a blitz with a hand blender or a trip in the food processor to turn it into a smooth puree (with a tbsp or 2 of milk if needed) whereas the squash is soft enough to beat to a puree with a big fork.
  3. Squeeze the roasted garlic out of their skins and into a small pan with the 25g butter with the sage and a good amount of seasoning – I am never brave enough with the salt but love my black pepper. Do as you please. When bubbling and well combined, take off the heat and pour two thirds into the squash, the rest into the celeriac puree. Mix well, taste for seasoning and be bold! It can take a fair amount to make their flavours come through in the final dish.
  4. Caramelise the onions (or buy a jar and skip this step). Melt the butter and oil then add in the onions and bay leaves – on a medium heat stir well until the onions are slick with oil and then turn the heat down to low, cover and cook for upto an hour until they are completely soft and translucent. You will need to check in on them to stir and ensure they aren’t sticking.
  5. When soft and clear, take off the lid and turn up the heat to drive off the liquid the onions will have produced.
  6. Sprinkle on the sugar then stir in well, adding in the Marsala at this point – cook stirring constantly for another 5-10 minutes until browned and sticky. They will have shrunk in volume quite considerably. Take off the heat and leave to cool.
  7. Make the pasta by putting all the ingredients into a large bowl, seasoning well and scrunching then kneading by hand. You may need a tbsp or two of cold water to help bring it all together. It will be very stiff but knead until smooth, cover with cling and give it one hour (although upto 3 days is fine) in the fridge to relax and chill. Make yourself a coffee and go do the same!
  8. Make the white sauce by melting the butter and adding in the flour, mustard powder, seasoning and nutmeg. Stir over a medium-high heat until foamy and then pour in the milk, bit by bit, stirring all the way to incorporate all the liquid. Turn the heat up to high and cook until thickened. Take off the heat and beat in the ricotta until smooth. Leave to cool.
  9. Remove the pasta dough from the fridge and roll out with a pasta machine until very thin – mine is from Lakeland and I took it to setting 6. This is less than a millimetre thick. Lay out on the (very clean) work surface or kitchen table, slicing pieces to fit your baking dish.
  10. Use a deep baking dish (mine is 8×10 inches and about 4-5 inches deep but just go with what you’ve got, even use two dishes if necessary). Now it’s time to layer everything up and bake. Using a third of everything (apart from the white sauce – you need to leave a quarter to top the dish with) layer butternut, pasta, caramelised onions, pasta, celeriac purée, pasta then white sauce and a tbsp of parmesan. Repeat twice more then top with the remaining white sauce, dried sage, black pepper and the remaining parmesan.
  11. Bake at 200°C for approximately 45 minutes until cooked through and browned on top. Leave to stand for at least ten minutes before cutting and serving as it will be piping hot.