- Preheat oven to 350°F. Line an 8 square baking pan with aluminum foil and spray with cooking spray.
- Melt chocolate over a double boiler or in the microwave and set aside to cool.
- With an electric mixer on medium, beat butter and sugar substitute until light and creamy, about 4 minutes. Turn speed down to low and beat in eggs, one at a time. Add melted chocolate and blend well. Add soy flour, water, sugar substitute and extracts; mix until just combined. Fold in nuts. Transfer batter to prepared pan.
- Bake 20 to 25 minutes, until a tester inserted in the center comes out with just a few crumbs. Cool and cut into 16 squares.