I'll post the recipes to the marshmallow and meyer lemon layers (I simplified both considerably), because I was satisfied with those. The strawberry layer turned out a wee bit icy (which some people claimed to like!), no doubt because I messed with it after it was "done" because it wasn't pink enough. So I kept adding more strawberry product until I liked the color.
Also of note: first, meyer lemons were cheaper at Wegmans than regular lemons, and I am glad, because I really think they do have a lovely flavor. Second, I had planned to put toasted sliced almonds at the bottom of the pans, but then I burnt my almonds. Arrgh. I still think that would be a good textural and flavor touch. The idea comes from the meyer lemon recipe, but I think it would be nice snug against a marshmallow layer.
To slice the semifreddos, turn them out of their pans and use a large knife dipped in hot water to cut 1 inch slices. Work fast! I served mine with sugared strawberries.
2 c chilled heavy whipping cream
14 oz marshmallow creme
With electric mixer, beat cream to soft peaks-- not past. Beat in marshmallow creme. This will require a lot of beating, so be sure to not beat it too much at first. It might never feel fully incorporated. Fine. Do not create marshmallow-flecked butter. Line a loaf pan with plastic wrap (leaving a generous overhang) or use a spring-form pan. Spread in pan and freeze till firm, at least 4 hours but up to 1 day.
Meyer Lemon Semifreddo
1 3/4 c chilled heavy whipping cream
1 1/4 c sugar
7 large egg yolks
1/2 c fresh Meyer lemon juice or regular lemon juice
1 T plus 2 t finely grated Meyer lemon peel or regular lemon peel
1/4 t salt
With electric mixer, beat cream to soft peaks. Refrigerate.
Whisk 1 1/4 c sugar, yolks, juice, zest, and salt in large metal bowl. Set bowl over large saucepan of simmering water. Whisk continuously until thick and fluffy, about 4 minutes. Remove bowl from over simmering water. Beat with mixer till thick, cool, and doubled in volume, about 6 minutes. Fold in chilled whipped cream. Transfer to loaf pan lined with plastic wrap (with a generous overhang). Tap lightly to remove air pockets. Cover and freeze until firm, 8 hours or overnight.