For cups, arrange 6 foil cupcake liners in muffin tins for support. In inverted cover of a TupperWave™ Stack Cooker, place white chocolate baking bar. Microwave on High 1 1/2 minutes until bar begins to melt. Stir to melt completely, then stir in almonds. Spoon one rounded tablespoon of the mixture into each of the 6 cups. Using a Tupperware® Sandwich Spreader, spread the mixture evenly on bottoms and up sides of cups. Chill cups until hardened, about l hour.

While the candy cups are chilling, prepare the filling: Put the egg yolk in a Thatsa™ Bowl Jr.. In a TupperWave™ 3-quart casserole. Put the semisweet chocolate, 1/2 cup of the heavy cream and the butter in a microwaveable dish and microwave on High for 2 to 3 minutes until the chocolate melts and the mixture is hot (do not let it boil). Stir several times to encourage the chocolate to melt. 

Using a Tupperware® Double-Sided Spatula, gradually stir about 1/2 of the hot chocolate mixture into the egg yolk. Cook on Medium (50% power) for 30 to 60 seconds until the mixture is just hot. Stir in the remaining 3 tablespooons of heavy cream.

Cover and chill until mixture is smooth and thickened, about 1 1/2 hours, stirring occasionally. (If butter separates out, it will blend again when mixture is stirred.)

With an electric mixer at medium speed, beat the chilled chocolate mixture until light and fluffy, about 2 minutes. Spoon or pipe the chocolate mixture into the chilled candy cups. Chill filled cups for at least 2 hours and up to 24 hours. To serve, let cups stand at room temperature 15 minutes. Garnish, if desired, with lace decorations.