Take a look at the TurboTax article below for step-by-step
instructions to enter your Back Door Roth contributions.
One key point to watch is entering your previous
non-deductible basis ($1100).
When all is done, you should see the total amount of
distributions from your Form 1099-R (both you and your spouse) reported on line
15a. Line 15b should be the sum of any
earnings in your IRA from the 2015 contribution that was invested plus $5500
(and earnings if any) from your wife’s deductible 2016 IRA contribution.
https://ttlc.intuit.com/replies/6768029
