Open-Faced Rye Sandwich with Liver Paste, Pickled Cucumbers, and Crispy Fried Onions

**Rye Bread Preparation:**

1. **Combine Dry Ingredients:** In a large mixing bowl, whisk together the rye flour, bread flour, instant yeast, salt, and caraway seeds.

2. **Add Water:** Gradually add the lukewarm water to the dry ingredients, mixing until a shaggy dough forms.

3. **Knead the Dough:** Turn the dough out onto a lightly floured surface and knead for 8-10 minutes, or until it becomes smooth and elastic. If the dough is too sticky, add a little more bread flour, one tablespoon at a time. Alternatively, use a stand mixer with a dough hook on medium-low speed for 6-8 minutes.

4. **First Proof:** Place the dough in a lightly oiled bowl, turning to coat. Cover the bowl with plastic wrap or a damp towel and let it rise in a warm place for 1-1.5 hours, or until doubled in size.

5. **Shape the Loaf:** Gently punch down the dough to release the air. Shape it into a round or oval loaf. Place the loaf on a baking sheet lined with parchment paper.

6. **Second Proof:** Cover the loaf with a damp towel and let it rise for another 30-45 minutes, or until slightly puffy.

7. **Preheat Oven:** Preheat your oven to 425°F (220°C).

8. **Bake the Bread:** Score the top of the loaf with a sharp knife or razor blade. Bake for 20-25 minutes, or until the crust is golden brown and the internal temperature reaches 200-210°F (93-99°C).

9. **Cooling:** Transfer the baked rye bread to a wire rack to cool completely before slicing.

**Crispy Fried Onions Preparation:**

1. **Prepare Onions:** Thinly slice the onion into rings. Separate the rings and place them in a bowl.

2. **Dredge the Onions:** In a separate small bowl, mix together the flour, salt, and pepper. Dredge the onion rings in the flour mixture, ensuring they are lightly coated. Shake off any excess flour.

3. **Heat the Oil:** Pour the vegetable oil into a large fry pan or deep fryer and heat over medium-high heat until it reaches 350°F (175°C). If you don't have a thermometer, test the oil by dropping a small piece of onion into it. If it sizzles and browns quickly, the oil is ready.

4. **Fry the Onions:** Carefully add the dredged onion rings to the hot oil in batches, being careful not to overcrowd the pan. Fry for 2-3 minutes per batch, or until they are golden brown and crispy.

5. **Drain the Onions:** Remove the fried onions from the oil with a slotted spoon and transfer them to a plate lined with paper towels to drain excess oil.

**Assemble the Open-Faced Sandwiches:**

1. **Slice the Bread:** Cut the cooled rye bread into approximately 1/2-inch thick slices.

2. **Spread the Liver Paste:** Spread a generous layer of liver paste onto each slice of rye bread.

3. **Add Pickled Cucumbers:** Arrange thinly sliced pickled cucumbers on top of the liver paste.

4. **Top with Fried Onions:** Generously sprinkle the crispy fried onions over the pickled cucumbers.

5. **Garnish (Optional):** Garnish with fresh parsley, if desired.

6. **Serve Immediately:** Serve the open-faced rye sandwiches immediately for the best flavor and texture.