Heat oven to 350. Have an 8" or 9" square baking pan ready. (Don't have to grease pan.)

Put chocolate and about 1/4 cup of the heavy cream in the pan. Place pan in the oven for 3 to 5 minutes (can be done while oven is heating). When cream just begins to bubble, remove pan and whisk until cream and chocolate have blended. If chocolate hasn't completely melted, return to oven for 1 to 2 minutes longer, then whisk.

Whisk in remaining cream until blended. Add sugar; whisk to blend, then whisk in eggs until smooth, stirring into corners of pan. Sprinkle with flour. Stir in with a rubber spatula, scraping sides and bottom of pan, until well blended.

Bake for 30 to 35 minutes until a pick inserted near the center comes out clean. Let cake cool in pan on a wire rack. Cut into 9 squares. Serve warm or at room temperature.