For the lemon cream: Combine the cream, confectioners' sugar, vanilla and lemon zest and beat to soft peaks with an electric mixer on medium-high speed. Add the sour cream and beat until smooth and stiff peaks. Refrigerate until ready to serve, up to 1 hour.
For the oatmeal berry cobbler: Preheat the oven to 375 degrees F.
In an 8-by-8-inch baking dish, mix together by hand the oats, brown sugar, baking powder, cinnamon and salt. Scatter half the berries evenly over the mixture.
In a mixing bowl, whisk together the eggs, buttermilk, butter, maple syrup and vanilla. Pour over the berries and dry ingredients. Finish by scattering the remaining berries on top, along with the chopped pecans.
Bake until set in the middle, about 20 minutes. Serve with the lemon cream.