Line an 8 by 8 baking pan with parchment paper. In a medium-heavy saucepan melt the butter over medium heat. Stir in the brown rice syrup with a wooden spoon or heatproof rubber spatula. Continue to stir constantly until the mixture reaches 270 degrees F on the candy thermometer. Be careful not to let the mixture burn. Once the mixture is hot enough, pour the toffee into the parchment-lined pan and allow it to cool.
While the toffee is cooling melt the chocolate over a double boiler or in a heatproof glass bowl set over a medium pot of boiling water not touching the bottom of the bowl. Pour the melted chocolate onto the cooled toffee and sprinkle with the almonds. Put the pan in the refrigerator and allow it to cool.
Once the toffee and chocolate is cooled break it into pieces and serve.