Yep, great place, been there sooo many times, it used to be free, now there's a small fee to pay at the entrance which also includes a visit to the museum of the Capuchins. You'll find there the
San Francesco in Meditazione (
San Francis in Prayer) painting from Caravaggio. [1]
The English Wikipedia reports it as a copy, but it is still debated if the original is the one in Santa Maria della Concezione dei Cappuccini (Our Lady of the Conception of the Capuchins) or the other one in Palazzo Barberini.
Fun fact: both paintings are in Piazza Barberini, a few hundred meters from each other.
[1] https://en.wikipedia.org/wiki/Saint_Francis_in_Prayer_(Carav...