Place the ricotta in a small strainer
set over a bowl and refrigerate for 30 minutes to drain
the excess liquid.
Transfer the drained ricotta to a food processor
, add the brown sugar
and orange liqueur, and process until smooth. (The ricotta mixture can be made up to 8 hours in advance, covered and kept refrigerated.)
Divide the strawberries
among 4 dessert bowls and top each with a 1/4 cup of the ricotta mixture and sprinkle with the pistachios.