How and where this income is entered will depend on how you are reporting the single member LLC. Unless an an S-Election was made, this income will be reported on a Schedule C.
To enter the income, enter schedulec in the search box and select the Jump to link in the search results.
Enter the income in the COMMON INCOME section under Other self-employed income, includes 1099-K, cash, and checks.
The income can be offset by reasonable and necessary business expenses incurred to generate the income.
For more information, see: Selling Homemade Goods on Etsy? Use this Tax Preparation Checklist - TurboTax Tax Tips & Videos