Okay, first thing's first: These were a project! The recipe is fairly simple ingredient-wise, but I don't have much experience with candies and their kin, so I found the procedure and flow very discombobulating. I felt like I needed to take notes and maybe draw up a little flow chart beforehand. I think it would be easier now that I've done it once, but I'm not sure how often, if ever, I'll be revisiting this recipe.

A few things I learned from this experience:

• I really need to get a candy thermometer if I'm going to keep doing things like this. The yogurt thermometer doesn't have a high enough range and the laser thermometer was giving some really weird readings, so I can't say I really trusted it.
• These little marshmallows take an absolute butt-load of sugar! So much sugar! Even if you think you've got plenty of sugar, you should probably get more.
• Frozen corn kernels or fresh corn-on-the-cob can be used for flavour the syrup.
• Cooking the oats in the water doesn't result in oat water or oat milk so much as oat gel.
• It takes A LOT of beating to sufficiently inflate and cool the marshmallow mixture.
• This recipe produces quite a few by-products: cooked corn, oatmeal, extra corn-flavoured simple syrup.

Cereal Marshmallows

Slightly adapted from Serious Eats

Ingredients

Corn-Flavoured Simple Syrup

• 2 1/2 c. water
• 1 c. frozen corn or 1 cob of corn, cut crosswise into several pieces
• 1/2 vanilla pod
• 510g sugar

Oat Water/Gel

• 2 c. water
• 28g rolled oats
• 1 vanilla pod, seeds scraped and reserved

Finished Marshmallows

• 21g gelatin
• 1/2 c. cold water
• 3/4 c. corn-flavoured simple syrup
• 1 c. oat water/gel
• 425g sugar
• vanilla seeds from 1 pod (reserved from oat water step above)
• 1/8 tsp. coarse sea salt
• 2 tsp. vanilla extract
• 1/16 tsp. almond extract

Directions

Corn-Flavoured Simple Syrup

1. Add corn to water and bring to a boil.
2. Cook until reduced by half (~30 minutes).
3. Remove corn from water.
4. Scrape seeds from vanilla pod and add them to the water.
5. Add the empty pod half as well.
6. Stir in sugar.
7. Continue boiling until mixture is thickened and slightly syrupy (~20 minutes).
8. Remove from heat and set aside.

Oat Water/Gel

1. Add oats and empty vanilla pod to water and bring to a boil.
2. Reduce heat to medium-low and simmer for ~10 minutes.
3. Strain liquid, pressing oats to remove as much liquid as possible.
4. You should have ~1 c. of liquid. If you have more, pour a little off, if you have less, add fresh water to bring it up to 1 c.

Finished Marshmallows

1. Place cold water in a large bowl and sprinkle with gelatin. Set aside.
2. Line two baking sheets with parchment paper (or silicone baking mats) and lightly grease the paper/mats.
3. Place the 3/4 c. corn-flavoured syrup, oat water/gel, sugar, salt, and vanilla seeds in a pot and bring to a boil.
4. Cook until temperature reaches 115°C (240°F).
5. Remove from heat and let stand until temperature reaches 99°C (210°F).
6. Pour hot mixture into bowl with gelatin.
7. Beat on medium-high speed until cooled and doubled in volume. This will take a long time. I didn't time it, but it was probably at least 10 minutes.
8. Toward the end of mixing, beat in the vanilla and almond extracts.
9. Pour mixture onto prepared baking sheets and spread to a thickness of 4-5mm.
10. Allow to sit, uncovered, in a well-ventilated area for 24 hours.
11. After 24 hours, peel the marshmallow sheets off the parchment paper/baking mats. !he top should be dry and somewhat crusty while the bottom will still be damp.
12. Place dry-side-down on a cutting board and cut into desired shapes.
13. Return to baking sheet (still dry-side-down) and allow to sit, uncovered, in a well-ventilated area for another 24 hours.
14. Once marshmallows are completely dry, they can be transferred to an air-tight container and stored for a few weeks at room temperature or indefinitely in the fridge or freezer.