Let's cut the ingredients for mixed tempura, kakiage. Slice the sweet potato into 5mm (0.2") slices. Stack the layers and chop them into 5mm (0.2") strips.
Slice the carrot into 5mm (0.2") slices. Stack the layers and chop them into 5mm (0.2") strips.
Chop off the stem ends of green beans. Trim off the other ends of the beans. Cut the green beans into 5cm (2") pieces.
Slice the onion into 5mm (0.2") slices.
Let's prepare tempura batter for kakiage. Sift the tempura flour into a bowl.
Add cold water. Stir lightly.
Place the vegetable strips into a bowl. Add a little tempura flour and toss to coat evenly.
Dip the vegetable strips into the tempura batter. Toss to coat well.
Measure the soba soup base in volume. Dilute the soup base with water.
Warm up the noodle soup in a pot.
Let's deep-fry the vegetable mixture at 170°C (338°F). Check if the oil is hot enough.
Place the vegetable mixture on a wooden rice paddle.
Gently slide the mixture into the oil. Keep the vegetable strips together.
Making holes in the kakiage helps its inside get crisp. Place another vegetable mixture. Make holes again.
Flip the kakiage over. Deep fry until both sides become golden brown.
Drain excess oil and place the kakiage on a cooling rack.
Let's preheat a noodle bowl with hot water. Be careful not to burn yourself.
Place a bundle of soba noodles in a large pot of boiling water. Gently separate the noodles evenly in boiling water.
When it reaches a full boil, immediately reduce heat to low. Adjust the heat and let the noodles circulate by itself in boiling water.
When the noodles are cooked, reheat the noodle soup. Drain and wash the noodles in running water. Then, immerse the noodles in icy water to improve the texture.
Drain the noodles well with a kitchen towel.
Pour hot water onto the soba noodles and warm them up. Drain the noodles again.
Transfer the noodles to the preheated bowl. Pour the hot noodle soup on the soba noodles.
Place 2 pieces of vegetable kakiage. Finally, sprinkle seven flavor chili pepper.
Hot soba noodles are often cooked about 30 seconds less time than cold soba noodles. As for frozen soba noodles, cook for about 30 seconds.
Enjoying soba noodles at the night of New Year's Eve is a traditional custom in Japan and it is also known as Toshikoshi soba.