1 ⅔cupsall-purpose flour (weigh or measure lightly)(210 grams)
½tspbaking soda
½tspcream of tartar
¼teaspoonsalt (my addition)
½tspground cinnamon
¼tspeach of nutmeg and ground cloves
⅓cupcup whole milk yogurt or sour cream(70 grams)
Lemon Batter
6tablespoonsunsalted butter, softened(84 grams)
1cupsugar(200 grams)
1tablespoonlemon zest
1tablespoonlemon juice
½teaspoonlemon extract (optional)
1 ⅔cupall-purpose flour (weigh or measure lightly)(210 grams)
½cupbaking soda
½tsp.cream of tartar
¼teaspoonsalt (increased from ⅛)
¾cupwhole milk yogurt or sour cream(170 grams)
3largeegg whites
2tablespoonsPowdered Sugar for Sprinkling
Instructions
Preheat oven to 350°. Grease and flour 9-inch Bundt pan (if you have one) or a standard size 10-inch Bundt.
Measure your dry ingredients (flour, baking soda, cream of tartar, salt, spices) for both batters and put them in separate bowls. This is mainly to get it out of the way. You can do it at another point of the recipe if you like.
Molasses Batter: Beat the butter and sugar until light and creamy, then add each egg yolk, one by one. Beat well, then pour in the molasses and beat until smooth.
Add the flour mixture alternately with the yogurt (or sour cream) mixing until combined. Set aside.
Lemon Batter: In a large bowl, cream the butter, sugar and lemon zest until very light. Beat in the lemon juice, then add the flour mixture to the batter, alternating with the yogurt or sour cream.
In a medium bowl, beat the egg whites until almost stiff peaks. Fold about ¼ of the beaten egg whites into the batter to lighten it up, then gently fold in the remaining whites. Note: My lemon batter was fairly dry, so I didn't worry too much about deflating the egg whites and just folded them in the best I could. The batter was still pretty light in the end.
Drop 3 or 4 large dollops of the lemon batter evenly around the bottom of the prepared pan. Top with 3 or 4 dollops of the molasses batter. Continue layering the batters.
Gently drop the pan once against the countertop to settle the batter some. Swirl the batters together with a butter knife, 2 or 3 swirls - don't overdo it or they'll mix together!
Bake for about 60 minutes (check at 50) or until cake appears set and edges are lightly browned.
Let cool in the pan on a rack for 15 minutes, then run the tip of a knife around the edges of the cake to loosen it. Turn out onto a rack to cool completely. Dust with powdered sugar.
Notes
If you don't have a scale and can't weigh out the flour, make sure to stir it well before measuring.