Sum spending and group for each month/category

[Roady]

Hi:

I have a spreadsheet for my spending. It has columns such as: category,
date, and $ amount. I want to be able to sum all spending by category for
each month. For example, it would auto-calc all Food expenses for May, all
Gas expenses for May, and then do the same for June, etc.

i have tried several combos of SUM, SUMIF, etc. but nothing works.
Recommendations?
Thanks, R