Creamy White Onion Soup

Ingredients

• 0.3 cup apple cider vinegar 
• 2 slices day-old brioche quartered
• 2  celery stalks chopped
• 0.3  cinnamon sticks 
• 0.5 cup cooking wine dry white
• 4 ounces fontina grated
• 1 tablespoon chives fresh chopped
• 4  garlic cloves 
• 2 tablespoons ginger peeled chopped
• 0.1 teaspoon ground allspice 
• 1 cup heavy cream 
• 6 servings kosher salt 
• 1  leek white thinly sliced
• 0.5 cup mirin 
• 0.3 cup olive oil 
• 1 medium onion red thinly sliced
• 0.1 teaspoon pepper flakes red crushed
• 0.5 cup red wine 
• 0.3 cup red wine vinegar 
• 1  serrano chile seeded chopped
• 2  shallots thinly sliced into rounds
• 0.5  star anise pod 
• 1 tablespoon sugar 
• 2 tablespoons butter unsalted
• 4 large onions white thinly sliced
• 0.3 cup citrus champagne vinegar 

Equipment

• bowl
• frying pan
• sauce pan
• pot
• blender

Directions

1. Place shallots in a small nonreactive bowl. Bring vinegars, sugar, and 1 cup water to a boil in a small saucepan, stirring to dissolve sugar.
2. Pour over shallots; chill.
3. DO AHEAD: Shallots can be pickled 5 days ahead. Cover and keep chilled.
4. Heat oil in a medium skillet over medium-high heat.
5. Add onion, season with salt, and cook, stirring often, until soft, 5-7 minutes.
6. Add wine, vinegar, sugar, cinnamon, star anise, red pepper flakes, and allspice. Bring to a boil, reduce heat, and simmer, stirring occasionally, until liquid is thickened and syrupy, 40-45 minutes.
7. DO AHEAD: Jam can be made 5 days ahead. Cover and chill.
8. Heat oil in a large pot over medium-high heat.
9. Add onions, leek, celery, garlic, chile, and ginger; season with salt. Cook, stirring often, until soft (do not let brown), 10-12 minutes.
10. Add wine and mirin to pot, bring to a boil,and cook until reduced by half, about 4 minutes. Reduce heat to medium, cover, and cook, stirring occasionally, until onions are soft and translucent, 25-30 minutes.
11. Let cool slightly, then purée in a blender until smooth. Strain into a large bowl and stir in cream (thin with water, if needed); season with salt. Reheat soup in a clean pot.
12. DO AHEAD: Soup can be made 2 days ahead.
13. Let cool; cover and chill.
14. Heat butter in a large skillet over medium heat. Cook bread until golden, about 3 minutes (you'll have 2 extra). Flip, top with cheese, cover, and cook until cheese is melted, about 4 minutes. Top toasts with pickled shallots and chives.
15. Spoon some jam into each bowl, pour soup around, and top with toasts.