In keeping with the italian theme:
Buy as much fennel as you think you need for amount of people eating
(you didn't mention # of people)
Remove fronds, cut off bottom end to get fresh end, then core the end.
Then cut bulbs vertically into oh, about 1" thick pieces. Salt & pepper to taste.
Saute in some butter and olive oil, just until getting slightly tender.
Then place all the fennel in a oblong baking dish, sprinkle liberally with
parmesan cheese and bake about 10 minutes,
until folk tender at 350 degrees, or until parm is slightly brown.
Or,
prep fennel as above, slice some onions like you would for a burger and
saute both until fennel in tender. Sprinkle with parmesan cheese and serve.
Or before serving, stick under the broiler to brown cheese alittle bit.