Peel the carrots and finely chop with the onion. De-skin the sausages by snipping the ends with kitchen scissors and peeling the casing off.
Heat a pan on a medium flame and pour in the oil. Add the onions and carrot to the pan and gently cook until browned and starting to soften. Then add the sausage meat, crumbling in using a wooden spoon, add the beef mince and let brown. Then add tinned tomatoes, ketchup or tomato paste, half a beef stock cube and a good glug of red wine. Season with salt and pepper, lots of mixed herbs and bring to the boil
Once boiling, turn to a simmer and leave for 20 minutes with the lid 3/4 of the way on. In the meantime, make the bechamel sauce. Tip creme fraiche into a bowl and crack in the egg, mix together. The mixture will be fairly thick so you'll want to add a dash of milk, just enough so it is a pourable liquid.
After 20 minutes, give the meat sauce a stir and taste to see if it needs more seasoning or even a dash of soy sauce if a bit bland. If it's looking too thick and congealing, add a dash of water. Bring to the boil and simmer for another 10 minutes. Your end result should be a fairly thick sauce but still with a small amount of liquid as to stop the lasagna from burning. Turn the heat off and put to one side when done.
Next, grab the dish you will be cooking the lasagna in (a wide, shallow dish is ideal) and put a thin layer of both sauces on the base to stop sticking. Don't worry about the sauces merging, it won't look pretty but it will taste great. Spread a good layer of pesto on the uncooked lasagna sheets and layer them into the dish, followed by the meat sauce, then white. Keep layering in this order: lasagna, pesto, meat sauce, white sauce. On the last layer, top with bechamel and a generous amount of two types of cheese. I recommend pecorino and cheddar, but feel free to go traditional and use some mozzarella.
When ready to cook, pop in the oven at 180C fan oven / 200C conventional oven / Gas Mark 6 for 45 minutes or until hot. I recommend covering this with a thin layer of foil as to avoid burning, taking off the foil only when melting the cheese at the last minute. If you do find it going a bit too brown do not fear, it will still taste great even if doesn't look it!
Enjoy your lasagna with extra cheese, pesto or a bit of basil. Great leftover the next day with a quick ping in the microwave, or can freeze portions for up to 6 months.