Preheat the oven to 180ºC, fan 160ºC, gas 4. Place the rhubarb in a shallow baking dish with the orange zest, juice and honey drizzled over the top. Cook for about 15 minutes, until soft.
Meanwhile, in a medium bowl, whisk the whipping cream to medium peaks and then fold in the custard. Fold in three quarters of the crushed ginger snaps.
Spoon the roasted rhubarb into 2 serving glasses. Top with the custard cream and sprinkle the remaining crushed ginger snaps over the top.