In a large heavy pot, on a medium heat add olive oil and diced onions, cook until the onions are translucent, stirring as needed. Add garlic and cook for another minute.
Add ground turkey a pound at a time, cook until all the turkey has browned and all the liquid has evaporated.
Add the tomato paste, stirring into the meat mix until the tomato paste darkens to a deep red. Add the dried basil and incorporate.
Add the crushed tomato one tin at a time and stir to incorporate. Add enough water to the pot to make the sauce loose. Bring to the boil reduce to a slow simmer.
Cook on a slow simmer for about 1 1/2 hours, skim every 1/2 hour to remove the oil & the fat from the meat. Before taking the sauce off the heat taste and add salt & pepper to your own taste.
Remember if you are using this as an ingredient in another recipe, you don't want to add to much salt or reduce the sauce to far. If you feel your sauce is too dry for lasagna add more water to loosen it up again.