Did Jesus perform a single miracle before his fast and temptation? Did Jesus perform a single miracle before his 40 day fast and temptation by the Devil?
None of the four Gospels record Jesus performing a miracle prior to his temptation in the wilderness.  Matthew, Mark, and Luke all record Jesus' baptism and immediately follow it with his temptation in the wilderness.  John does not mention the temptation: after Jesus's baptism, he begins calling his disciples and then performs "the first of his signs" – the replacing of water with wine (John 2:1–12).

On its face, this may seem conclusive, but we must remember that (1) the gospels are not exhaustive accounts of all the things Jesus did (see John 21:25) and (2) the gospels do not necessarily record all the events of the narrative in strict chronological order.  Here, it's particularly relevant to compare Luke 4:1–5:11 with John 1:35–2:12.  Luke records several miracles taking place before the first disciples are called, while John puts the first miracle after Peter and others have joined him.  

Despite these caveats, it still seems quite unlikely that the miracle of the wine or any other miracle took place before the temptation of Jesus.  Thus, while a dogmatic statement appears risky, concluding that Jesus performed no miracles before his temptation stands to reason.