heat oven 425 F. lightly butter ramekins;coat insides with sugar substitute. set aside on baking sheet
melt chocolate, butter and orange extract in a small saucepan over low heat. ( or microwave for one and a half minutes till butter is melted). transfer to medium bowl. whisk in the eggs yolks; set aside
combine the egg whites and cream of tartar in another bowl ans whip on high till frothy. slowly add the sugar substitute; whip until soft peaks form, about three minutes. fold one-third of wgg whites into chocolate mixture;gently fold in the remaining whites. divide batter among ramekins;bake until puffed and set, about 13 to 15 minutes. serve right away.