Congratulations on your first year. I think that with 350 sales you are off to a WONDERFUL start.
I have a bit different take on the discount/coupon thing. I don't offer discounts or coupons. I feel that I have a great product and if people like it they will return - and they won't need a coupon/discount to make that happen. I've been on etsy about 3 years and each year the number of return customers increases significantly. It will happen over time. I think that you will notice over your next year that you will have MANY return customers.
I do think, however, with edible items, it would be a great idea for you to include a small "freebie" with each purchase...maybe something new you are trying out...or something completely different than what is being purchased. Getting to taste something new (and FREE) is a wonderful way to encourage repeat customers.
Also, you mentioned sending recipes to customers. Instead, I would suggest that you consider selling a few recipes on your website. Others have great luck selling recipes...it would be a way to capture some new customers (and some who might never purchase the actual food). I've branched out, myself, into some digital artwork (coloring pages), and have had great luck with it. Nothing beats a sale where all you have to do is email a file.... and then you sell the file again...and again...and again!
Happy sales!