How do I make growixir?

Read the recipe as described in the first hint if you don't know it is.

You need a broken egg shell, cooked spaghetti, and horn ashes.

The broken shell comes from a hatching animal.

Use the boa-boa shell -- the "Read this!" hints in the TOWN section tells you
how to do that.  The broken shell will be on the floor.

You can find the spaghetti in the store.  And there's equipment to boil it.

Start by turning on the faucet with the left hand and carrying the water in
the bowl under the faucet with the right hand.  Dump it in the kettle.

Then add in the spaghetti.

And light the burner with the lighter that's just underneath.

For the horn ashes, put the horn (from the store) in the ashtray.