Heat the grill. Boil the pasta according to
pack instructions, then tip into a colander
and cool under gently running water.
Meanwhile, grill the bacon on a baking tray
until golden and crisp at the edges. When
almost ready, tip the walnuts onto the tray
to toast a little. Snip the bacon into strips.
Mix the lemon zest and juice, Parmesan
and oil in a large bowl. Season with pepper,
then tip in the spinach, tortellini, bacon
and walnuts. Toss well, add the ricotta in
small blobs, then gently toss. Season to taste,
then serve with a drizzle more oil and more
Parmesan, if you like.