In a saucepan combine sweet and sour cherries, water and lemon juice, bring to a boil. Mix together granulated sugar and cornstarch. When the fruit mixture comes to a boil, make a slurry - take 2 tablespoons of the cherry juice from the pot and stir it into the sugar mixture. Pour the slurry back into the pot (this will help prevent clumps in your filling)

Stir until thickened and cook for one minute longer. Take off the heat and set aside to cool.

Preheat the oven to 350°, place chopped pecans on a cookie sheet and bake for five minutes. While that's baking, cut cold butter. With hands mix butter, flour, sugar, cinnamon, nutmeg and toasted pecans until you get a crumbly sand consistency. Set aside.

In the bowl of a stand mixer, add sugar and lemon zest. Massage sugar and zest with your fingers to release the oils. Add room temp butter and mix on medium high for two minutes until the mixture is pale yellow. Scrape down the sides of the bowl and add eggs and mix. Add vanilla, sour cream and mix until combined. Scrape down the sides again then add flour mixture and mix to combine.

Butter and lightly flour a 9-inch tube pan. Set aside.

Spread half the batter in the bottom of the pan. Spoon cherry filling on top. Evenly spread remaining batter on top and sprinkle with pecan topping.

Bake at 350 for 35 to 40 minutes or until golden brown. When you touch the center of the cake it should spring back. Cool completely and serve at room temperature.