Huge zucchini

I had this problem last night...I made zucchini soup! I cooked 1/2 onion + 2-3 cloves garlic in olive oil, then added the chopped up monster zucchini, water to cover and 1 parmesan rind. I cooked until the zucchini softened then blended (after fishing out parmesan rind) with my immersion blender. I added a lot of basil chiffonade, white pepper, a bit of salt, and the juice of 1/2 lemon. I served with a dollop of plain yoghourt, a drop of extra virgin olive oil and more basil. No leftovers.

I am not sure if I am right about this, but I think overgrown zucchini may be the same as "marrow" in the UK (or at least is interchangeable with it?)--so maybe if you look for British recipes for "marrow" you will find something...I suppose it's big enough that you can experiment...

When in abundance, I grate and freeze zucchini in muffin tins. Then I can take a puck or two out, thaw and drain whenever I want some. Aside from quick breads and muffins, I really like to brown it a bit and scramble into some eggs for breakfast.

Zucchini chocolate cake is my favorite way to use up zucchini. There are lots of recipes online, but I've tried this one (minus the frosting) and it's delicious: http://www.kingarthurflour.com/recipes/chocolate-zucchini-cake-recipe

Here is a classic from Julia Child. Make sure you scoop the seeds out https://food52.com/recipes/18672-julia-child-s-tian-de-courgettes-au-riz-zucchini-tian

Melissa Clark's Zuchinni Tian (http://www.nytimes.com/recipes/1014910/zucchini-tian-with-curried-bread-crumbs.html) uses up a fair bit of zuchinni and is delicious to boot. The Kitchn's Zuchinni Butter also reduces a huge zuchinni to reasonable amount of spread (http://www.thekitchn.com/recipe-jennie-cooks-zucchini-b-121770)

A friend with a large garden slices "baseball bat" zucchini length wise into slices, grills them on both sides , and then uses them instead if lasagna noodles...very tasty

This will give you the general idea. A little bit of work, but they're delicious!
http://www.saveur.com/article/Recipes/Stuffed-Eggplant-Papoutsakia

I wish he lived up the road from me. Make
papoutsakia
(just google it)
Greek for little shoes. I think it's normally made with eggplant boats but zucchini would be fine too.

Make zucchini bread.

Grate it and make zucchini bread or make zucchini butter:
https://food52.com/recipes/23071-jennie-cook-s-zucchini-butter

My mom used to split them lengthwise, scrape the seeds and some of the middle out and stuff it with a good meat sauce, bake it and grate parm on top. I still do this, but with the little ones. I think stuffed zucchini was popular in the seventies. :)