Preheat oven to 325 F.
In a medium bowl, whisk together flour, 3/4 c. sugar, baking powder, and salt.
In a very large bowl, whisk together oil, egg yolks, and milk until well-combined.
Whisk in flour mixture until just incorporated.
In a separate bowl, whip egg whites with a mixer on high speed until frothy.
Add cream of tartar and vanilla bean paste or extract; beat until soft peaks form.
Gradually add remaining 3/4 cup granulated sugar, beating until stiff, glossy peaks form, about 5 minutes.
Fold one-third of the egg whites into batter.
Gently fold in remaining egg-white mixture with a rubber spatula.
Carefully pour batter into tube pan.
Bake for 45-55 minutes, or until top of cake springs back when touched.
Remove from oven, and let cool upside down (on a glass bottle) 1 hour.
To make the filling, beat cream, sugar, and vanilla together until medium peaks form.
Slide a thin knife around edges of tube and side of pan.
Cut cake horizontally into 3 layers with a serrated knife.
Place bottom layer to a serving plate.
Spread thin layer of whipped cream on cake.
Add half strawberries over whipped cream.
Top with another thin layer of whipped cream.
Add middle layer, and repeat with remaining whipped cream and strawberries.
Top with remaining cake layer.
Chill cake at least 1 hour.
Sprinkle with confectioners' sugar just before serving, if desired.