Separate the egg whites from the yolks. Reserve the yolks for another use and beat the egg whites until frothy in a stand mixer fitted with a whisk attachment, or using a hand mixer.
Add the cream of tartar and 3/4 cup of the sugar, 1 tablespoon at time, while the mixer is on med/high. Beat until stiff peaks are formed and sugar is dissolved, about 7-8 minutes. The meringue will be glossy, white and smooth.
Trace six 4-inch hearts onto parchment paper using a cookie cutter or by freehand. Pipe meringue mixture onto the parchment in a single layer, filling in the heart shapes.
Around the edges, pipe small dollops to form a raised edge.
Bake at 250F (120C) degrees for one hour. After an hour, turn the oven off and allow the meringues to sit in the oven for another hour while it cools.
Slice all the strawberries.
To make the strawberry juice, add 1 tablespoon of sugar to about 1/2 pound of the sliced strawberries with 1 tablespoon and mash until pulverized.
To make the whipped cream, add 1 cup heavy cream with 1/4 cup sugar and 1 teaspoon vanilla. Whip until desired consistency.
Remove the meringues from the oven and pipe in the whipped cream to the centers.
Top with sliced strawberries and reserved strawberry juice.