But others were horrified at the thought of combining pasta with Marmite - one calling it "an abomination".
Lawson wrote online: "So many of you know and love this already, and the rest of you are probably horrified by it: #RecipeOfTheDay is Spaghetti with Marmite. (Australians may obviously use Vegemite).
"And Italians, don't shout at me: this comes via the great Anna del Conte!"
Lawson created the recipe with the help of the Italian food writer, whose memoir "Risotto with Nettles" also included the recipe.
It's inspired by a traditional pasta dish made the day after a roast, in which spaghetti is tossed in meat stock.
And while Lawson admitted the combo sounds odd, she "hasn't found a child who doesn't like it".
Many of her followers were thrilled with the recipe, with one writing: "It is wonderful. The ultimate comfort food. A delicious lunch treat".
Another said they cooked it for their partner for lunch, who is now a "Marmite convert".
"Also adding wine and bacon make it taste even better. Such an easy meal to cook."
"This has been THE go to recipe I've used for 10 years now when I need to whip up a meal in 10 mins, but am too exhausted to do anything more than boil pasta," another commented.
But others were appalled by the dish, one claiming: "I just recoiled in horror at this. However, my dear wife has just grinned and said, 'It's on the menu soon'."
Another said, "I am absolutely appalled, Nigella! Vegemite on buttered toast is divine but with pasta?"
But they added that they'd be willing to try it, saying: "Last year when we went to London we went to Lina Stores on your and Anna's recommendation - it was fantastic, so I will give this recipe a go!"