Serves 8 1 hour 30 mins, cook 2 hours (plus draining and resting)
If you are time-poor, use bought pasta sheets.
For curd, wet the base of a large heavy-based saucepan, pour in milks and cream and place over high heat. Combine yoghurt and 1 tsp salt. Bring the milk mixture to the boil and allow it to rise up the sides of the saucepan, stir in yoghurt and reduce heat to low-medium. Without stirring, gently spin the saucepan and bring just back to boiling. Stand for 1 hour, strain through a muslin-lined sieve, tie up corners of muslin and allow the curds to drain for at least 6 hours.
For pasta, place all the ingredients and ½ tsp salt in a bowl and knead until mixture forms a ball. Place in an airtight container and rest for 1 hour. Remove and knead until smooth, flatten into a disc and rest again for 30 minutes. Divide dough into 3 and, using a pasta machine with rollers at widest setting, working with one piece at a time, feed dough through the rollers. Fold the dough in half lengthways and repeat rolling, reducing settings notch by notch, feeding and rolling until setting number 2 is reached. Roll pasta through twice. If you have been able to make the pasta without flouring it, then the consistency is perfect. Pasta sheets may be floured, placed on a tray, covered and refrigerated overnight.
For spinach filling, place lentils in a saucepan, cover with 5mm salted water and simmer over low-medium heat, topping up water to ensure constant level, for 1¼ hours. Drain, reserving cooking liquid. Bring a large pot of salted water to the boil. Add spinach and blanch for 30 seconds, then remove with a slotted spoon and refresh in iced water. Drain, squeezing to remove excess water, and coarsely chop. Heat butter in a wide saucepan over high heat until nut brown, add curry leaves (be careful: they will spit), add garlic and stir until it begins to colour. Add onion and cook until brown and soft. Add cooked lentils, spices, season to taste with salt and stir to combine. Reserve 1½ tbsp of this mixture for sauce. Stir in spinach and set aside.
For tomato sauce, preheat oven to 200C. Using a knife, remove tomato cores and score bases with a cross. Place scored-side up in a roasting pan and drizzle with 100ml oil. Roast tomatoes for 25-30 minutes or until skins have blackened, peel and coarsely chop. Heat remaining oil in a saucepan, add garlic and saut until it just begins to colour. Add tomatoes and cook, stirring occasionally, for 10-15 minutes or until thick.
Bring 750ml of salted water to the boil over high heat, pour into a stainless steel bowl placed over a pot of simmering water. Whisk in polenta in a fine stream, then stir over low heat for 20 minutes or until thick. Whisk in ¼ of goat's curd. Bring a large pot of salted water to the boil, add pasta sheets and cook for 8 minutes, drain and lay on a clean tea towel.
Lightly butter a 20cmx30cm baking dish. Trim pasta to fit and lay a piece over the base, pour over polenta and lightly indent with fingertips to hold tomato sauce, then top with half the tomato sauce. Cover with another pasta sheet, then spinach and lentils. Top with remaining pasta. Pulse remaining room temperature curd in a food processor until smooth, spread over lasagne and sprinkle with extra polenta. At this stage the lasagne may be refrigerated for up to 2 days.
Preheat oven to 200C. Cut lasagne into eight portions and bake for 35-40 minutes or until golden. Meanwhile, combine remaining tomato sauce, reserved lentil mixture and some lentil cooking water in a saucepan and bring to a simmer. Serve lasagne drizzled with lentil sauce.