How can I get into the city?

Hint 1 of 14:

First of all, have you delivered the letter to the farmer?

Hint 2 of 14:

When you talk to him, he'll tell you something important about the guards.

Hint 3 of 14:

They like sandwiches!

Hint 4 of 14:

Perhaps you can make a sandwich for them.  You have a sandwich spell in your
spell book.

Hint 5 of 14:

There are tricks to getting all of the ingredients to the potion -- those
are covered in other hints in this section.  If you don't know how to find 
any of the items mentioned below, look for other questions that might help.

Hint 6 of 14:

The lettuce can be found in the garden next to the farmer's house.

Hint 7 of 14:

The ground wheat can be made from grain from the meadow.

Hint 8 of 14:

Use it on the water wheel to grind the whole stalks.

Hint 9 of 14:

Make cheese in the basement of the farmer's house.

Hint 10 of 14:

And the farmer has a recipe for mustard.

Hint 11 of 14:

You first need to grind a radish from the garden.  If you have the lettuce
and wheat, then you know how to get ground radish.

Hint 12 of 14:

Then add the vinegar (which is sitting near the farmer) as the farmer told
you to -- click it on the bowl with the ground radish.