Bring the heavy cream to a simmer in a small saucepan. Put the chopped chocolate in a medium bowl, pour the hot cream over it and let sit for 3 minutes to allow the chocolate to melt. Add the salt and whisk until the ganache is completely smooth. Transfer half of the ganache to a separate bowl. Stir the orange oil into one bowl and the chopped toffee into the other. Transfer each flavor of ganache to a separate pastry bag fitted with a large round tip.
Line a sheet pan with parchment paper. Pipe 1 1/2-inch chocolate hearts on the sheet pan. Allow the hearts to sit at cool room temperature to set up, or let them set up in the refrigerator before serving.