Strawberry-Rhubarb Mousse Pie

1 pound rhubarb, cut into 1-inch chunks (3 1/2 cups)
1 cup sugar
2 envelopes unflavored gelatin
1 pint strawberries, hulled
1 tablespoon lemon juice
2 cups shortbread cookie crumbs (about 36 1
1/2-inch-square cookies)
6 tablespoons margarine or butter (3/4 stick), melted
1/2 pint heavy or whipping cream
mint sprigs and strawberries for garnish
 
In 2-quart saucepan, heat rhubarb, sugar, and 1/4 cup water to boiling over high heat, stirring constantly. Reduce heat to medium-low and continue cooking until rhubarb is very tender, about 10 minutes. In food processor, with knife blade attached, blend rhubarb until smooth; return rhubarb to saucepan.

Sprinkle gelatin over 1/2 cup cold water; let stand 2 minutes to soften.

In bowl, with potato masher or fork, mash strawberries. Stir softened gelatin, mashed strawberries, and lemon juice into rhubarb; cook 3 minutes.

Pour rhubarb mixture into bowl and refrigerate, stirring occasionally, until mixture mounds slightly when dropped from a spoon, about 2 1/2 hours. (Or, for quicker setting, place bowl with rhubarb mixture in a larger bowl of ice water and stir every 10 minutes until mixture mounds, about 1 hour.)

Meanwhile, preheat oven to 350 degrees F. In deep-dish 9-inch pie plate, with hand, mix cookie crumbs with margarine or butter. Press mixture onto bottom and up side of pie plate. Bake 15 minutes or until golden; cool on wire rack.

When rhubarb mixture is ready, beat cream until stiff peaks form. With spatula, fold whipped cream into rhubarb mixture until blended. Spoon mixture into pie shell. Refrigerate 3 hours or overnight until pie is well chilled and set. Garnish with mint and strawberries to serve.